AY Honors/Trees - Advanced/Answer Key

3. Separately collect, press, mount, and label specimens that demonstrate the following terms:

a. Serrate

The margins of the leaf have forward-pointing teeth.

b. Doubly serrate

The serrations on the margin of the leaf have serrations on them.

c. Entire

The entire margin of the leaf is smooth. (sassafras, pawpaw)

d. Crenate

The margins of the leaf have rounded teeth.

e. Dentate

The margins of the leaf have symmetrical teeth.

f. Lobe

The edges of the leaf have large, smooth indentations that do not go all the way to the centerline. (oaks)

g. Incise

h. Whorled

i. Opposite

Leaves are paired on opposite sides of the stem. (sumacs, hickorys, walnut)

j. Alternate

Leaves are not across from one another on the stem, but are offset relative to one another.

k. Pinnately compound

A leaf consisting of multiple leaflets. (sumac, locust)

l. Triple compound (if possible)

Like pinnately compund leaves except the leaflets have leaflets of their own. (devil's walking stick, mimosa).

8. Define the following terms:

a. Stipule

b. Petiole

c. Blade

d. Pitch

e. Heartwood

f. Sapwood

g. Springwood

h. Summerwood

i. Annual ring

j. Cambium

k. Xylem

l. Phloem

9. What families of trees have:

a. Thorns

b. Catkins

c. Winged seeds

d. Acorns

e. Pods

f. Capsules

h. Berries

g. Nuts