The Plants of Michigan Part 39

7b. Leaves sharply or sinuately toothed --9.

8a. Stem erect, simple or sparingly branched =Good King Henry, Chenopodium bonus-henricus.=

8b. Stem diffuse or ascending, freely branched =Orache, Atriplex patula.=

9a. Flowers in small heads, in the axils or in terminal spikes; leaves sinuately toothed or nearly entire =Strawberry Blite, Chenopodium capitatum.=

9b. Flowers in terminal panicles; leaves sharply toothed (Goosefoot) --10.

10a. Panicles short, not as long as the subtending leaves =Goosefoot, Chenopodium murale.=

10b. Panicles long, exceeding the subtending leaves --11.

11a. Calyx green =Goosefoot, Chenopodium urbic.u.m.=

11b. Calyx red =Goosefoot, Chenopodium rubrum.=

12a. Foliage glandular and strongly aromatic --13.

12b. Foliage not glandular nor aromatic; sometimes ill-scented --15.

13a. Flowers in large loose open spreading panicles; leaves deeply pinnatifid =Jerusalem Oak, Chenopodium botrys.=

13b. Flowers cl.u.s.tered in slender axillary or terminal spikes --14.

14a. Spikes dense, leafy =Mexican Tea, Chenopodium ambrosioides.=

14b. Spikes open, nearly leafless =Wormseed, Chenopodium ambrosioides var. anthelmintic.u.m.=

15a. Stem erect, 5-20 dm. tall; leaves frequently white-mealy =Lamb's Quarters, Chenopodium alb.u.m.=

15b. Stem prostrate or ascending, succulent; leaves glaucous-white beneath =Goosefoot, Chenopodium glauc.u.m.=

15c. Stem widely and diffusely branched; leaves green, soon deciduous =Cycloloma, Cycloloma atriplicifolium.=

AMARANTHACEAE, the Amaranth Family

Herbs, with alternate leaves, and inconspicuous greenish or reddish flowers without petals, which are axillary or in dense cl.u.s.ters, blooming in summer.

1a. Flower-cl.u.s.ters axillary --2.

1b. Flower-cl.u.s.ters in terminal spikes or panicles, sometimes also axillary --3.

2a. Plant prostrate or dec.u.mbent; seed about 1.5 mm. broad =Pigweed, Amaranthus blitoides.=

2b. Plant erect or ascending, widely branched; seeds about 1 mm.

broad (3-10 dm. high) =Tumble Weed, Amaranthus graecizans.=

3a. Princ.i.p.al leaves with a pair of spines at their base =Th.o.r.n.y Amaranth, Amaranthus spinosus.=

3b. Spines none at the base of the leaves --4.

4a. Weedy plants of cultivated or waste ground; flowers monoecious or polygamous; pistillate flowers with a calyx (Pigweed) --5.

4b. Plants of swamps or stream-banks; flowers dioecious; pistillate flowers without calyx (Water Hemp) --7.

5a. Spikes short, 1-8 cm. long, crowded in dense ovoid panicles; the terminal spike not conspicuously elongated beyond the appressed or ascending lower ones =Pigweed, Amaranthus retroflexus.=

5b. Spikes slender, 1-12 cm. long; the terminal spike greatly exceeding the short inconspicuous divergent lower ones --6.

6a. Bracts subulate, sharply awned =Pigweed, Amaranthus hybridus.=

6b. Bracts merely ac.u.minate =Pigweed, Amaranthus paniculatus.=

7a. Flowers in leafy spikes, or the lower in separate cl.u.s.ters =Water Hemp, Acnida tuberculata.=

7b. Flowers in separate distinct cl.u.s.ters =Water Hemp, Acnida tuberculata var. subnuda.=

PHYTOLACCACEAE, the Pokeweed Family

Herbs with alternate entire leaves, small flowers without petals, and a many-celled ovary.

One species in Michigan, 1-2 m. high, with numerous racemes of whitish flowers, in late summer, followed by dark-purple berries =Pokeweed, Phytolacca decandra.=

NYCTAGINACEAE, the Four-o'Clock Family

Herbs, with opposite entire leaves and flowers in small cl.u.s.ters surrounded by a broad open calyx-like involucre; the true calyx colored like a corolla; petals none (4-8 dm. high; flowers purple, in summer).

1a. Leaves lanceolate or narrower, sessile =Umbrella-wort, Oxybaphus hirsutus.=

1b. Leaves ovate, petioled =Umbrella-wort, Oxybaphus nyctagineus.=

ILLECEBRACEAE, the Knotwort Family