203 
found in many woods. As to the texture, whether hard or soft, 
experience again is the best guide; however if a wood can be 
easily indented with the finger nail it may be called a soft wood ; 
weight as here used is comparative and can be determined only 
by using different kinds of wood. As in the use of any key the 
more one knows, the easier it is to use. | 
In using the key always begin with number 1, read both a and 
b; after determining in which group the particular specimen 
belongs turn to the number indicated and read both a and b, 
choosing the one which best describes the specimen; continue 
this process until the name is secured. Accuracy in observation 
and in following the key is of first importance. 
I а. In smooth cross section growth rings are conspicuously marked by a zone of 
large pores collected in the spring wood, alternating with a zone of denser 
summer wood with smaller pores; pores usually visible without dup 
ur cc ea See soam ELM Des Е NUT cor e ne 
b. In smooth cross section the growth rings are not marked by a zone of A 
ais the are Wood ав Та э... иеа I5. 
28. rub rays аена broad, at least as broad as the large pores, con- 
spicuous without magnifier; radiating and branching lines or patches in 
khe СНЕ WOOL. Lo rli adir cut gine E a E au 
0 Woods fob compictely ag та ао ee 4. 
ga. Wood vith reddish tinge.: 1... ens ш ек. Red Oaks. (Quercus.) 
b. Wood dingy, not with reddish tinge.............. White Oaks. (Quercus.) 
4 a. Wood golden-colored or yellowish-b ller pores in summer 
ood appearing, without magnifier, as lighter colored specks or lines. . . 5. 
b. od not golden or yellowish 
а. Pores in summer wood single or in small groups, not in conspicuously con- 
centric lines; pith rays fine, conspicuous only with magnifier; large pores 
опе filled... v o Lor es Black Locust. (Robinia pseudacacia.) 
b. Pores in summer wood usually in clusters appearing as irregular, concentric 
lines; pith rays conspicuous without magnifier...... Mulberry. (Morus.) 
- Wood reddish, pink, or salmon-colored; pores in summer wood conspicuous, 
often arranged in irregular concentric lines; pores in spring wood usually 
in two or more rows, the large pores sometimes filled. 
Thorny Locust. (Gleditsia triacanihos.) 
ood not completely as in a....... 
wood 
л 
© 
& 
| МООЛ MOL completely asi оон o CE. Lied dei ug 
. Pores in summer small, appearing as conspicuous concentric, wavy 
lines, sometimes continuous, often rail-fence like; wood comparatively 
„Ре! ode i. f ОИСИ ишы тыш б E Mu иык ырык NM E ME 8. 
-I 
a 
b. Pores in summer wood not completely asin а@...:;...................... 
8 a. Wood greenish-white; the be иа rays pets as broad as the large pores. 
Hackberry. (Celtis.) 
b. Wood not greenish-white; pith rays not as broad as the large pores. 
Elm. (Ulmus.) 
