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A3IARAXTHACEAE, the Amaranth Family 



Herbs, with alternate leaves, and inconspicuous greenish or red- 

 dish flowers without petals, which are axillary or in dense clusters, 

 blooming in summer. 



la. Flower-clusters axillary 2. 



Ib. Flower-clusters in terminal spikes or panicles, sometimes also 

 axillary 3. 



2a. Plant prostrate or decumbent; seed about 1.5 mm. broad 



Pigweed, Amaranthus blitoides. 



2b. Plant erect or ascending, w r idely branched ; seeds about 1 

 mm. broad (3 10 dm. high) 



Tumble Weed, Amaranthus graecizans. 



3a. Principal leaves with a pair of spines at their base 



Thorny 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; pistil- 

 late flowers without calyx (Water Hernp) 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 ex- 

 ceeding the short inconspicuous divergent lower ones 6. 



6a. Bracts subulate, sharply awned 



Pigweed, Amaranthus hybridus. 

 6b. Bracts merely acuminate. Pigweed, Amaranthus paniculatus. 



7a. Flowers in leafy spikes, or the lower in separate clusters 



Water Hemp, Acnida tuberculata. 

 7b. Flowers in separate distinct clusters 



Water Hemp. Acnida tuberculata Tar. 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. 



