purple; flowers in loose clusters
=Crane's-bill, Geranium bicknellii.=

RUTACEAE, the Rue Family

Shrubs or low trees, with compound leaves frequently dotted with
translucent glands; flowers small, greenish-white, with 3-5 sepals,
petals, and stamens.

1a. Leaflets 5-9; stems thorny =Prickly Ash, Zanthoxylum americanum.=

1b. Leaflets 3; stems not thorny =Hop Tree, Ptelea trifoliata.=

SIMARUBACEAE, the Quassia Family

Trees, with pinnately compound leaves and small greenish-yellow flowers
in large panicles in early summer, ripening into winged fruits.

One species in Michigan, escaped from cultivation chiefly in towns
=Tree of Heaven, Ailanthus glandulosa.=

POLYGALACEAE, the Milkwort Family

Small herbs, with alternate or whorled simple leaves, and small
irregular flowers; sepals 5, petals 3, stamens 6 or 8, more or less
united with each other and with the petals.

1a. All of the leaves alternate --2.

1b. Some or all of the leaves in whorls (1-4 dm. high; flowers greenish,
purple, or white; summer) (Milkwort) --6.

2a. Flowers few, loosely clustered, 15-20 mm. long (1-3 dm. high;
flowers purple; early summer)
=Flowering Wintergreen, Polygala paucifolia.=

2b. Flowers numerous, in a spike or raceme --3.

3a. Stem-leaves minute, linear-subulate; stem slender, erect, 3-7 dm.
high (flowers pink; summer) =Milkwort, Polygala incarnata.=

3b. Stem-leaves narrowly oblong or broader; stem generally 1-4 dm. high
--4.

4a. Flowers in a short thick obtuse very dense spike (flowers
greenish or purple; summer) =Milkwort, Polygala sanguinea.=

4b. Flowers in a slender tapering spike --5.

4c. Flowers in a raceme; plants with subterranean flowers also
(flowers purple; early summer) =Milkwort, Polygala polygama.=

5a. Leaves linear or nearly so (flowers purple; summer) --7b.

5b. Leaves lanceolate or oblong-lanceolate, 2-6 cm. long (flowers white;
late spring) =Seneca Snakeroot, Polygala senega.=

5c. Leaves ovate to ovate-lanceolate (flowers white; late spring)
=Seneca Snakeroot, Polygala senega var. latifolia.=

6a. Spike oval, thick, obtuse =Milkwort, Polygala cruciata.=

6b. Spike acute --7.

7a. Spike densely flowered, 1-2 cm. long