id
stringlengths
24
24
title
stringclasses
442 values
context
stringlengths
151
3.71k
question
stringlengths
12
270
answers
dict
56fa02638f12f3190063006f
Wood
It is remarkable that the inner heartwood of old trees remains as sound as it usually does, since in many cases it is hundreds, and in a few instances thousands, of years old. Every broken limb or root, or deep wound from fire, insects, or falling timber, may afford an entrance for decay, which, once started, may penet...
What growth stage of insects bore holes into trees?
{ "answer_start": [ 356 ], "text": [ "larvae" ] }
56fa02638f12f31900630070
Wood
It is remarkable that the inner heartwood of old trees remains as sound as it usually does, since in many cases it is hundreds, and in a few instances thousands, of years old. Every broken limb or root, or deep wound from fire, insects, or falling timber, may afford an entrance for decay, which, once started, may penet...
What part of a tree often stays impressively sound even when hundreds or thousands of years old?
{ "answer_start": [ 26 ], "text": [ "inner heartwood" ] }
56fa02638f12f31900630071
Wood
It is remarkable that the inner heartwood of old trees remains as sound as it usually does, since in many cases it is hundreds, and in a few instances thousands, of years old. Every broken limb or root, or deep wound from fire, insects, or falling timber, may afford an entrance for decay, which, once started, may penet...
What evidence do some insect larvae leave in a tree forever?
{ "answer_start": [ 409 ], "text": [ "tunnels" ] }
56fa04db8f12f31900630095
Wood
If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside...
In what stage of its life does a tree usually grow the fastest?
{ "answer_start": [ 133 ], "text": [ "youth" ] }
56fa04db8f12f31900630096
Wood
If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside...
As a tree ages, do its growth rings usually get wider or narrower?
{ "answer_start": [ 243 ], "text": [ "narrower" ] }
56fa04db8f12f31900630097
Wood
If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside...
What part of a tree opens and spreads out more as it matures?
{ "answer_start": [ 543 ], "text": [ "crown" ] }
56fa04db8f12f31900630098
Wood
If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside...
Is wood production of a tree lessened or increased as it ages?
{ "answer_start": [ 601 ], "text": [ "lessened" ] }
56fa04db8f12f31900630099
Wood
If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside...
Along with nutrients, what do trees growing in forests have to compete for?
{ "answer_start": [ 776 ], "text": [ "light" ] }
56fa0745f34c681400b0bf5d
Wood
Different pieces of wood cut from a large tree may differ decidedly, particularly if the tree is big and mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other trees, the reverse applies. This may or may not correspo...
When a big tree is cut up, will the pieces of wood differ or all be the same?
{ "answer_start": [ 51 ], "text": [ "differ" ] }
56fa0745f34c681400b0bf5e
Wood
Different pieces of wood cut from a large tree may differ decidedly, particularly if the tree is big and mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other trees, the reverse applies. This may or may not correspo...
In a large log, will the heartwood or sapwood usually be stronger and tougher?
{ "answer_start": [ 510 ], "text": [ "heartwood" ] }
56fa0745f34c681400b0bf5f
Wood
Different pieces of wood cut from a large tree may differ decidedly, particularly if the tree is big and mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other trees, the reverse applies. This may or may not correspo...
If you need really hard, strong wood from a small tree, would it likely be better to use the heartwood or sapwood?
{ "answer_start": [ 368 ], "text": [ "sapwood" ] }
56fa0745f34c681400b0bf60
Wood
Different pieces of wood cut from a large tree may differ decidedly, particularly if the tree is big and mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other trees, the reverse applies. This may or may not correspo...
Besides big trees, what trees are more likely to have a range of different kinds of wood?
{ "answer_start": [ 105 ], "text": [ "mature" ] }
56fa09098f12f3190063009f
Wood
In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous (see section of yew log above). This is produced by deposits in the heartwood of chemical substances, so that a dramatic co...
When trees have a visible difference in color between sapwood and heartwood, which is darker?
{ "answer_start": [ 95 ], "text": [ "heartwood" ] }
56fa09098f12f319006300a0
Wood
In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous (see section of yew log above). This is produced by deposits in the heartwood of chemical substances, so that a dramatic co...
What is deposited naturally in heartwood that changes its color?
{ "answer_start": [ 278 ], "text": [ "chemical substances" ] }
56fa09098f12f319006300a1
Wood
In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous (see section of yew log above). This is produced by deposits in the heartwood of chemical substances, so that a dramatic co...
Is the color difference between heartwood and sapwood usually very subtle or conspicuous?
{ "answer_start": [ 185 ], "text": [ "conspicuous" ] }
56fa09098f12f319006300a2
Wood
In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous (see section of yew log above). This is produced by deposits in the heartwood of chemical substances, so that a dramatic co...
What type of properties of heartwood and sapwood is often the same even if their colors are very different?
{ "answer_start": [ 378 ], "text": [ "mechanical" ] }
56fa09098f12f319006300a3
Wood
In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous (see section of yew log above). This is produced by deposits in the heartwood of chemical substances, so that a dramatic co...
Although heartwood and sapwood might be similar mechanically, if their colors are very different, what other type of difference would they have?
{ "answer_start": [ 459 ], "text": [ "chemical" ] }
56fa0bfa8f12f319006300b3
Wood
Some experiments on very resinous Longleaf Pine specimens indicate an increase in strength, due to the resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps o...
What type of tree has resin that makes it stronger when it dries?
{ "answer_start": [ 34 ], "text": [ "Longleaf Pine" ] }
56fa0bfa8f12f319006300b4
Wood
Some experiments on very resinous Longleaf Pine specimens indicate an increase in strength, due to the resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps o...
What's the funny name for resin-saturated heartwood?
{ "answer_start": [ 190 ], "text": [ "fat lighter" ] }
56fa0bfa8f12f319006300b5
Wood
Some experiments on very resinous Longleaf Pine specimens indicate an increase in strength, due to the resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps o...
What is fat lighter practically impervious to in addition to termites?
{ "answer_start": [ 261 ], "text": [ "rot" ] }
56fa0bfa8f12f319006300b6
Wood
Some experiments on very resinous Longleaf Pine specimens indicate an increase in strength, due to the resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps o...
If spruce is shot full of crude resin and dried, which of its properties is increased?
{ "answer_start": [ 558 ], "text": [ "strength" ] }
56fa0bfa8f12f319006300b7
Wood
Some experiments on very resinous Longleaf Pine specimens indicate an increase in strength, due to the resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps o...
Since it's highly flammable, what do people often use little pieces of longleaf pine tree stumps for?
{ "answer_start": [ 392 ], "text": [ "kindling" ] }
56fa0e0df34c681400b0bf8d
Wood
Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a f...
Which of the wood in a growth ring is usually darker?
{ "answer_start": [ 10 ], "text": [ "latewood" ] }
56fa0e0df34c681400b0bf8e
Wood
Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a f...
Which property of a tree's wood that gives clues about its strength and hardness can be judged by it's color?
{ "answer_start": [ 120 ], "text": [ "density" ] }
56fa0e0df34c681400b0bf8f
Wood
Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a f...
What category of trees show this difference greatly?
{ "answer_start": [ 221 ], "text": [ "coniferous" ] }
56fa0e0df34c681400b0bf90
Wood
Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a f...
What type of woods might sometimes appear to have darker earlywood on a finished surface?
{ "answer_start": [ 242 ], "text": [ "ring-porous" ] }
56fa0e0df34c681400b0bf91
Wood
Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a f...
With the exception of earlywood/latewood difference in some types of trees, how much of an indication of strength is a wood's color?
{ "answer_start": [ 494 ], "text": [ "no indication" ] }
56fa104bf34c681400b0bf97
Wood
Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an ...
What condition does an abnormal color usually indicate in wood?
{ "answer_start": [ 47 ], "text": [ "diseased" ] }
56fa104bf34c681400b0bf98
Wood
Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an ...
What other property can you assume of wood that is diseased?
{ "answer_start": [ 78 ], "text": [ "unsoundness" ] }
56fa104bf34c681400b0bf99
Wood
Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an ...
What causes the black checked pattern in the wood of western hemlocks?
{ "answer_start": [ 143 ], "text": [ "insect attacks" ] }
56fa104bf34c681400b0bf9a
Wood
Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an ...
What animals cause the reddish-brown streaks of color in hickory wood?
{ "answer_start": [ 265 ], "text": [ "birds" ] }
56fa104bf34c681400b0bf9b
Wood
Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an ...
What's the name for the pretty coloring effect caused in some wood by rot-producing fungi?
{ "answer_start": [ 551 ], "text": [ "spalting" ] }
56fa115c8f12f319006300bd
Wood
In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried retains 8–16% of the water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry.
What does wood retain in its cell walls despite being air-dried?
{ "answer_start": [ 112 ], "text": [ "water" ] }
56fa115c8f12f319006300be
Wood
In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried retains 8–16% of the water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry.
Air-dried wood keeps up to what percentage of the water in its cell walls?
{ "answer_start": [ 101 ], "text": [ "16" ] }
56fa115c8f12f319006300bf
Wood
In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried retains 8–16% of the water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry.
What kind of dried wood retains a small quantity of water but is considered absolutely dry?
{ "answer_start": [ 193 ], "text": [ "oven-dried" ] }
56fa142af34c681400b0bfa1
Wood
The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on rawhide, paper, or cloth. Within certain limits, the greater the water content, the greater its softening effect.
Often the water in wood makes it more pliable and what else?
{ "answer_start": [ 80 ], "text": [ "softer" ] }
56fa142af34c681400b0bfa2
Wood
The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on rawhide, paper, or cloth. Within certain limits, the greater the water content, the greater its softening effect.
What material sometimes used for dog chews reacts similarly to wood because of its water content?
{ "answer_start": [ 183 ], "text": [ "rawhide" ] }
56fa142af34c681400b0bfa3
Wood
The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on rawhide, paper, or cloth. Within certain limits, the greater the water content, the greater its softening effect.
What material we use to write or print on, like wood, becomes softer and more pliable when wet?
{ "answer_start": [ 192 ], "text": [ "paper" ] }
56fa142af34c681400b0bfa4
Wood
The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on rawhide, paper, or cloth. Within certain limits, the greater the water content, the greater its softening effect.
When water content increases within certain limits in wood, does is have a less or greater softening effect?
{ "answer_start": [ 267 ], "text": [ "greater" ] }
56fa142af34c681400b0bfa5
Wood
The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on rawhide, paper, or cloth. Within certain limits, the greater the water content, the greater its softening effect.
What type of action does water create in cloth?
{ "answer_start": [ 154 ], "text": [ "softening" ] }
56fa160f8f12f319006300c3
Wood
Drying produces a decided increase in the strength of wood, particularly in small specimens. An extreme example is the case of a completely dry spruce block 5 cm in section, which will sustain a permanent load four times as great as a green (undried) block of the same size will.
What will drying often increase in wood?
{ "answer_start": [ 42 ], "text": [ "strength" ] }
56fa160f8f12f319006300c4
Wood
Drying produces a decided increase in the strength of wood, particularly in small specimens. An extreme example is the case of a completely dry spruce block 5 cm in section, which will sustain a permanent load four times as great as a green (undried) block of the same size will.
What color is also used interchangeably with "undried" for wood?
{ "answer_start": [ 235 ], "text": [ "green" ] }
56fa160f8f12f319006300c5
Wood
Drying produces a decided increase in the strength of wood, particularly in small specimens. An extreme example is the case of a completely dry spruce block 5 cm in section, which will sustain a permanent load four times as great as a green (undried) block of the same size will.
What type of wood can hold four times as much of a load when dried?
{ "answer_start": [ 144 ], "text": [ "spruce" ] }
56fa184cf34c681400b0bfab
Wood
The greatest strength increase due to drying is in the ultimate crushing strength, and strength at elastic limit in endwise compression; these are followed by the modulus of rupture, and stress at elastic limit in cross-bending, while the modulus of elasticity is least affected.
What type of "ultimate" strength is one of the two types increased the most by drying wood?
{ "answer_start": [ 64 ], "text": [ "crushing" ] }
56fa184cf34c681400b0bfac
Wood
The greatest strength increase due to drying is in the ultimate crushing strength, and strength at elastic limit in endwise compression; these are followed by the modulus of rupture, and stress at elastic limit in cross-bending, while the modulus of elasticity is least affected.
What property of wood is least affected by drying?
{ "answer_start": [ 250 ], "text": [ "elasticity" ] }
56fa184cf34c681400b0bfad
Wood
The greatest strength increase due to drying is in the ultimate crushing strength, and strength at elastic limit in endwise compression; these are followed by the modulus of rupture, and stress at elastic limit in cross-bending, while the modulus of elasticity is least affected.
Is strength at elastic limit in endwise compression or stress at elastic limit in cross-bending increased more by drying wood?
{ "answer_start": [ 87 ], "text": [ "strength at elastic limit in endwise compression" ] }
56fa184cf34c681400b0bfae
Wood
The greatest strength increase due to drying is in the ultimate crushing strength, and strength at elastic limit in endwise compression; these are followed by the modulus of rupture, and stress at elastic limit in cross-bending, while the modulus of elasticity is least affected.
Is the strength of the modulus of rupture or elasticity increased more when wood is dried?
{ "answer_start": [ 163 ], "text": [ "modulus of rupture" ] }
56fa19cc8f12f319006300c9
Wood
Wood is a heterogeneous, hygroscopic, cellular and anisotropic material. It consists of cells, and the cell walls are composed of micro-fibrils of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%).
Along with hygroscopic, cellular, and anisotropic, how is the material of wood described?
{ "answer_start": [ 10 ], "text": [ "heterogeneous" ] }
56fa19cc8f12f319006300ca
Wood
Wood is a heterogeneous, hygroscopic, cellular and anisotropic material. It consists of cells, and the cell walls are composed of micro-fibrils of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%).
What does wood consist of?
{ "answer_start": [ 88 ], "text": [ "cells" ] }
56fa19cc8f12f319006300cb
Wood
Wood is a heterogeneous, hygroscopic, cellular and anisotropic material. It consists of cells, and the cell walls are composed of micro-fibrils of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%).
What part of wood's cells are composed of cellulose and hemicellulose?
{ "answer_start": [ 108 ], "text": [ "walls" ] }
56fa19cc8f12f319006300cc
Wood
Wood is a heterogeneous, hygroscopic, cellular and anisotropic material. It consists of cells, and the cell walls are composed of micro-fibrils of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%).
What makes up 40-50% of the cell walls in wood?
{ "answer_start": [ 147 ], "text": [ "cellulose" ] }
56fa19cc8f12f319006300cd
Wood
Wood is a heterogeneous, hygroscopic, cellular and anisotropic material. It consists of cells, and the cell walls are composed of micro-fibrils of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%).
What substance is hemicellulose impregnated with?
{ "answer_start": [ 216 ], "text": [ "lignin" ] }
56fa1c3d8f12f319006300d3
Wood
In coniferous or softwood species the wood cells are mostly of one kind, tracheids, and as a result the material is much more uniform in structure than that of most hardwoods. There are no vessels ("pores") in coniferous wood such as one sees so prominently in oak and ash, for example.
What type of cells makes up most wood cells in coniferous trees?
{ "answer_start": [ 73 ], "text": [ "tracheids" ] }
56fa1c3d8f12f319006300d4
Wood
In coniferous or softwood species the wood cells are mostly of one kind, tracheids, and as a result the material is much more uniform in structure than that of most hardwoods. There are no vessels ("pores") in coniferous wood such as one sees so prominently in oak and ash, for example.
Are hardwood or softwood species more uniform in structure?
{ "answer_start": [ 17 ], "text": [ "softwood" ] }
56fa1c3d8f12f319006300d5
Wood
In coniferous or softwood species the wood cells are mostly of one kind, tracheids, and as a result the material is much more uniform in structure than that of most hardwoods. There are no vessels ("pores") in coniferous wood such as one sees so prominently in oak and ash, for example.
What are the visible vessels in hardwoods commonly called?
{ "answer_start": [ 199 ], "text": [ "pores" ] }
56fa1c3d8f12f319006300d6
Wood
In coniferous or softwood species the wood cells are mostly of one kind, tracheids, and as a result the material is much more uniform in structure than that of most hardwoods. There are no vessels ("pores") in coniferous wood such as one sees so prominently in oak and ash, for example.
What hardwood that starts with the letter "O" would have pores?
{ "answer_start": [ 261 ], "text": [ "oak" ] }
56fa1c3d8f12f319006300d7
Wood
In coniferous or softwood species the wood cells are mostly of one kind, tracheids, and as a result the material is much more uniform in structure than that of most hardwoods. There are no vessels ("pores") in coniferous wood such as one sees so prominently in oak and ash, for example.
Besides oak, what's an example of a hardwood with prominent pores?
{ "answer_start": [ 269 ], "text": [ "ash" ] }
56fa1d25f34c681400b0bfb3
Wood
The structure of hardwoods is more complex. The water conducting capability is mostly taken care of by vessels: in some cases (oak, chestnut, ash) these are quite large and distinct, in others (buckeye, poplar, willow) too small to be seen without a hand lens. In discussing such woods it is customary to divide them int...
Is the structure of hardwood simple or complex?
{ "answer_start": [ 35 ], "text": [ "complex" ] }
56fa1d25f34c681400b0bfb4
Wood
The structure of hardwoods is more complex. The water conducting capability is mostly taken care of by vessels: in some cases (oak, chestnut, ash) these are quite large and distinct, in others (buckeye, poplar, willow) too small to be seen without a hand lens. In discussing such woods it is customary to divide them int...
What handles most of the water conduction in hardwoods?
{ "answer_start": [ 103 ], "text": [ "vessels" ] }
56fa1d25f34c681400b0bfb5
Wood
The structure of hardwoods is more complex. The water conducting capability is mostly taken care of by vessels: in some cases (oak, chestnut, ash) these are quite large and distinct, in others (buckeye, poplar, willow) too small to be seen without a hand lens. In discussing such woods it is customary to divide them int...
Are the vessels in chestnut wood large or small?
{ "answer_start": [ 163 ], "text": [ "large" ] }
56fa1d25f34c681400b0bfb6
Wood
The structure of hardwoods is more complex. The water conducting capability is mostly taken care of by vessels: in some cases (oak, chestnut, ash) these are quite large and distinct, in others (buckeye, poplar, willow) too small to be seen without a hand lens. In discussing such woods it is customary to divide them int...
In wood from a willow tree, what would you need to use to see the tiny vessels?
{ "answer_start": [ 248 ], "text": [ "a hand lens" ] }
56fa1d25f34c681400b0bfb7
Wood
The structure of hardwoods is more complex. The water conducting capability is mostly taken care of by vessels: in some cases (oak, chestnut, ash) these are quite large and distinct, in others (buckeye, poplar, willow) too small to be seen without a hand lens. In discussing such woods it is customary to divide them int...
Besides ring-porous, what's the other class hardwoods are often divided into?
{ "answer_start": [ 357 ], "text": [ "diffuse-porous" ] }
56fa1ee4f34c681400b0bfbd
Wood
In ring-porous species, such as ash, black locust, catalpa, chestnut, elm, hickory, mulberry, and oak, the larger vessels or pores (as cross sections of vessels are called) are localised in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, ...
What species of hardwood are hickory and mulberry trees?
{ "answer_start": [ 3 ], "text": [ "ring-porous" ] }
56fa1ee4f34c681400b0bfbe
Wood
In ring-porous species, such as ash, black locust, catalpa, chestnut, elm, hickory, mulberry, and oak, the larger vessels or pores (as cross sections of vessels are called) are localised in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, ...
In what season do the growth-rings of ring-porous species form with larger vessels localized?
{ "answer_start": [ 228 ], "text": [ "spring" ] }
56fa1ee4f34c681400b0bfbf
Wood
In ring-porous species, such as ash, black locust, catalpa, chestnut, elm, hickory, mulberry, and oak, the larger vessels or pores (as cross sections of vessels are called) are localised in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, ...
In what season does the part of the growth-ring with smaller vessels form in ring-porous species?
{ "answer_start": [ 332 ], "text": [ "summer" ] }
56fa1ee4f34c681400b0bfc0
Wood
In ring-porous species, such as ash, black locust, catalpa, chestnut, elm, hickory, mulberry, and oak, the larger vessels or pores (as cross sections of vessels are called) are localised in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, ...
What fibers does the summer's section of growth-ring have more of?
{ "answer_start": [ 403 ], "text": [ "wood fibers" ] }
56fa1ee4f34c681400b0bfc1
Wood
In ring-porous species, such as ash, black locust, catalpa, chestnut, elm, hickory, mulberry, and oak, the larger vessels or pores (as cross sections of vessels are called) are localised in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, ...
Along with strength, what property do wood fibers lend to wood?
{ "answer_start": [ 470 ], "text": [ "toughness" ] }
56fa2008f34c681400b0bfc7
Wood
In diffuse-porous woods the pores are evenly sized so that the water conducting capability is scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are alder, basswood,[citation needed] birch, buckeye, maple, willow,and the Populus species such as aspen, cottonw...
What kind of woods have pores that are uniformly sized?
{ "answer_start": [ 3 ], "text": [ "diffuse-porous" ] }
56fa2008f34c681400b0bfc8
Wood
In diffuse-porous woods the pores are evenly sized so that the water conducting capability is scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are alder, basswood,[citation needed] birch, buckeye, maple, willow,and the Populus species such as aspen, cottonw...
What species do aspen, cottonwood, and poplar trees belong to?
{ "answer_start": [ 282 ], "text": [ "Populus" ] }
56fa2008f34c681400b0bfc9
Wood
In diffuse-porous woods the pores are evenly sized so that the water conducting capability is scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are alder, basswood,[citation needed] birch, buckeye, maple, willow,and the Populus species such as aspen, cottonw...
With walnut, what's another tree in the intermediate group?
{ "answer_start": [ 369 ], "text": [ "cherry" ] }
56fa2008f34c681400b0bfca
Wood
In diffuse-porous woods the pores are evenly sized so that the water conducting capability is scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are alder, basswood,[citation needed] birch, buckeye, maple, willow,and the Populus species such as aspen, cottonw...
What capability is spread through the growth ring in ring-porous species?
{ "answer_start": [ 63 ], "text": [ "water conducting" ] }
56fa2008f34c681400b0bfcb
Wood
In diffuse-porous woods the pores are evenly sized so that the water conducting capability is scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are alder, basswood,[citation needed] birch, buckeye, maple, willow,and the Populus species such as aspen, cottonw...
Is maple wood diffuse-porous or ring-porous?
{ "answer_start": [ 3 ], "text": [ "diffuse-porous" ] }
56fa21cdf34c681400b0bfd1
Wood
In temperate softwoods there often is a marked difference between latewood and earlywood. The latewood will be denser than that formed early in the season. When examined under a microscope the cells of dense latewood are seen to be very thick-walled and with very small cell cavities, while those formed first in the sea...
What kind of softwoods often have significant differences in their earlywood and latewood?
{ "answer_start": [ 3 ], "text": [ "temperate" ] }
56fa21cdf34c681400b0bfd2
Wood
In temperate softwoods there often is a marked difference between latewood and earlywood. The latewood will be denser than that formed early in the season. When examined under a microscope the cells of dense latewood are seen to be very thick-walled and with very small cell cavities, while those formed first in the sea...
Is latewood denser or less dense than earlywood?
{ "answer_start": [ 111 ], "text": [ "denser" ] }
56fa21cdf34c681400b0bfd3
Wood
In temperate softwoods there often is a marked difference between latewood and earlywood. The latewood will be denser than that formed early in the season. When examined under a microscope the cells of dense latewood are seen to be very thick-walled and with very small cell cavities, while those formed first in the sea...
Does strength come from the walls or cavities of wood cells?
{ "answer_start": [ 388 ], "text": [ "walls" ] }
56fa21cdf34c681400b0bfd4
Wood
In temperate softwoods there often is a marked difference between latewood and earlywood. The latewood will be denser than that formed early in the season. When examined under a microscope the cells of dense latewood are seen to be very thick-walled and with very small cell cavities, while those formed first in the sea...
Are the cell walls of earlywood thick or thin?
{ "answer_start": [ 329 ], "text": [ "thin" ] }
56fa21cdf34c681400b0bfd5
Wood
In temperate softwoods there often is a marked difference between latewood and earlywood. The latewood will be denser than that formed early in the season. When examined under a microscope the cells of dense latewood are seen to be very thick-walled and with very small cell cavities, while those formed first in the sea...
What general size are the cavities in the cells of very dense latewood?
{ "answer_start": [ 259 ], "text": [ "very small" ] }
56fa236c8f12f319006300dd
Wood
If a heavy piece of pine is compared with a lightweight piece it will be seen at once that the heavier one contains a larger proportion of latewood than the other, and is therefore showing more clearly demarcated growth rings. In white pines there is not much contrast between the different parts of the ring, and as a r...
Comparing a heavy and a lightweight piece of wood from a pine, which would have a greater proportion of latewood?
{ "answer_start": [ 5 ], "text": [ "heavy" ] }
56fa236c8f12f319006300de
Wood
If a heavy piece of pine is compared with a lightweight piece it will be seen at once that the heavier one contains a larger proportion of latewood than the other, and is therefore showing more clearly demarcated growth rings. In white pines there is not much contrast between the different parts of the ring, and as a r...
What feature of a piece of pine with more latewood would be more clear and pronounced?
{ "answer_start": [ 213 ], "text": [ "growth rings" ] }
56fa236c8f12f319006300df
Wood
If a heavy piece of pine is compared with a lightweight piece it will be seen at once that the heavier one contains a larger proportion of latewood than the other, and is therefore showing more clearly demarcated growth rings. In white pines there is not much contrast between the different parts of the ring, and as a r...
What type of tree has very little contrast between parts of its growth rings?
{ "answer_start": [ 230 ], "text": [ "white pines" ] }
56fa236c8f12f319006300e0
Wood
If a heavy piece of pine is compared with a lightweight piece it will be seen at once that the heavier one contains a larger proportion of latewood than the other, and is therefore showing more clearly demarcated growth rings. In white pines there is not much contrast between the different parts of the ring, and as a r...
Is white pine easy or difficult to work with because of its texture?
{ "answer_start": [ 369 ], "text": [ "easy" ] }
56fa236c8f12f319006300e1
Wood
If a heavy piece of pine is compared with a lightweight piece it will be seen at once that the heavier one contains a larger proportion of latewood than the other, and is therefore showing more clearly demarcated growth rings. In white pines there is not much contrast between the different parts of the ring, and as a r...
What kind of pines have very deep, darkly colored hardwood that stands out against the light earlywood?
{ "answer_start": [ 386 ], "text": [ "hard pines" ] }
56fa254bf34c681400b0bfdb
Wood
It is not only the proportion of latewood, but also its quality, that counts. In specimens that show a very large proportion of latewood it may be noticeably more porous and weigh considerably less than the latewood in pieces that contain but little. One can judge comparative density, and therefore to some extent stren...
Having a high proportion of latewood isn't all that matters; what else is important?
{ "answer_start": [ 56 ], "text": [ "quality" ] }
56fa254bf34c681400b0bfdc
Wood
It is not only the proportion of latewood, but also its quality, that counts. In specimens that show a very large proportion of latewood it may be noticeably more porous and weigh considerably less than the latewood in pieces that contain but little. One can judge comparative density, and therefore to some extent stren...
What can we judge in wood just by looking at it?
{ "answer_start": [ 265 ], "text": [ "comparative density" ] }
56fa254bf34c681400b0bfdd
Wood
It is not only the proportion of latewood, but also its quality, that counts. In specimens that show a very large proportion of latewood it may be noticeably more porous and weigh considerably less than the latewood in pieces that contain but little. One can judge comparative density, and therefore to some extent stren...
What property of wood could we project some indication of by looking at its density?
{ "answer_start": [ 315 ], "text": [ "strength" ] }
56fa254bf34c681400b0bfde
Wood
It is not only the proportion of latewood, but also its quality, that counts. In specimens that show a very large proportion of latewood it may be noticeably more porous and weigh considerably less than the latewood in pieces that contain but little. One can judge comparative density, and therefore to some extent stren...
What could we call some specimens with a high proportion of latewood that explains why they weigh less than specimens with much less latewood?
{ "answer_start": [ 163 ], "text": [ "porous" ] }
56fa29d8f34c681400b0bfe3
Wood
No satisfactory explanation can as yet be given for the exact mechanisms determining the formation of earlywood and latewood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very ...
What facet of wood is affected to some degree by the place where the tree grows?
{ "answer_start": [ 443 ], "text": [ "character" ] }
56fa29d8f34c681400b0bfe4
Wood
No satisfactory explanation can as yet be given for the exact mechanisms determining the formation of earlywood and latewood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very ...
If you want wood that's easy to work with, what kind of growth would you want the tree to have?
{ "answer_start": [ 631 ], "text": [ "moderate to slow" ] }
56fa29d8f34c681400b0bfe5
Wood
No satisfactory explanation can as yet be given for the exact mechanisms determining the formation of earlywood and latewood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very ...
What species of tree can be said to growth ring proportions that aren't determined just by their rate of growth?
{ "answer_start": [ 162 ], "text": [ "conifers" ] }
56fa29d8f34c681400b0bfe6
Wood
No satisfactory explanation can as yet be given for the exact mechanisms determining the formation of earlywood and latewood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very ...
What counterpart of earlywood are scientists still trying to explain the formation of?
{ "answer_start": [ 116 ], "text": [ "latewood" ] }
56fa29d8f34c681400b0bfe7
Wood
No satisfactory explanation can as yet be given for the exact mechanisms determining the formation of earlywood and latewood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very ...
While there is some relationship between where and how a tree grows, what can't anyone formulate to govern it?
{ "answer_start": [ 512 ], "text": [ "a rule" ] }
56fa2ab88f12f319006300e7
Wood
In ring-porous woods each season's growth is always well defined, because the large pores formed early in the season abut on the denser tissue of the year before.
What kind of woods always have very clearly marked seasonal growth?
{ "answer_start": [ 3 ], "text": [ "ring-porous" ] }
56fa2ab88f12f319006300e8
Wood
In ring-porous woods each season's growth is always well defined, because the large pores formed early in the season abut on the denser tissue of the year before.
What size pores form early in ring-porous woods' growing season?
{ "answer_start": [ 78 ], "text": [ "large" ] }
56fa2ab88f12f319006300e9
Wood
In ring-porous woods each season's growth is always well defined, because the large pores formed early in the season abut on the denser tissue of the year before.
When does the denser tissue the new pores abut come from?
{ "answer_start": [ 146 ], "text": [ "the year before" ] }
56fa2d76f34c681400b0bfed
Wood
In the case of the ring-porous hardwoods there seems to exist a pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. T...
Ring-porous hardwoods have a clear relationship between their properties and what other factor?
{ "answer_start": [ 101 ], "text": [ "rate of growth" ] }
56fa2d76f34c681400b0bfee
Wood
In the case of the ring-porous hardwoods there seems to exist a pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. T...
Is harder, heavier wood indicated by narrower or wider growth rings?
{ "answer_start": [ 239 ], "text": [ "wider" ] }
56fa2d76f34c681400b0bfef
Wood
In the case of the ring-porous hardwoods there seems to exist a pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. T...
What kind of wood with a name that starts with "H" is a ring-porous hardwood?
{ "answer_start": [ 400 ], "text": [ "hickory" ] }
56fa2d76f34c681400b0bff0
Wood
In the case of the ring-porous hardwoods there seems to exist a pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. T...
If the growth rings are wider, was the growth of the tree slower or more rapid?
{ "answer_start": [ 210 ], "text": [ "more rapid" ] }
56fa2d76f34c681400b0bff1
Wood
In the case of the ring-porous hardwoods there seems to exist a pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. T...
What is the only kind of wood that will definitely be harder and stronger when it grows faster?
{ "answer_start": [ 364 ], "text": [ "ring-porous" ] }
56fa3006f34c681400b0bff7
Wood
In ring-porous woods of good growth it is usually the latewood in which the thick-walled, strength-giving fibers are most abundant. As the breadth of ring diminishes, this latewood is reduced so that very slow growth produces comparatively light, porous wood composed of thin-walled vessels and wood parenchyma. In good ...
Which specific type of wood within ring-porous woods have more fibers to make it strong?
{ "answer_start": [ 54 ], "text": [ "latewood" ] }