NEBRASKA WiLD-DUCK FOODS. 



57 



SUBMEBGED PLANTS. 



27. Variable pondweed {Potamogeton heter- 



ophyllus). 



28. Curly pondweed (Potamogeton per- 



foliatus richardsonii) . Common. 



29. Bushy pondweed (Xaja* flexilis). 



30. "Water smart-weed (Polygonum amphi- 



iium). 



31. White water crowfoot {Batrachium 



divaricatum) .* Common. 



32. Coontail {Ceratophylliim demersum). 



33. Spatterdock (NympJiaea advena). 



Algae abundant. 



Dominants: 



22. Musk grass {Chara sp.). 



23. Small pondweed {Potamogeton pusil- 



lus). 



24. Waterweed (Philotria canadensis).* 



Flowers ; only place found in this 

 group of lakes in eastern Cherry 

 County. 

 Secondary species: 



25. Water moss (Drepanocladus sp.). 



Abundant. 



26. Sago pondweed {Potamogeton pectina- 



tus). Abundant. 



Wild-duck foods. — Plants in the above list which have considerable value as 

 food for wild ducks are: Nos. 2 (16), 4 (20), 22, 23, 26, 27, 29, and 32; those 

 of less importance are: Nos. 1 (18), 5 (17), 13, 19, 21 (30), 24, 28, 31, and 

 83 ; the remainder are of no known value. 



TWENTY-ONE LAKE, CHERRY COUNTY. 



September 6, 1915. 



Description. — Marshy at west end. Water perhaps a little alkaline ; average 

 greatest depth, 7J to 8 feet ; bottom, sandy. No inlet or outlet. 



DlSTBIBUTION OF VEGETATION. 

 SHOEE PLANTS. 



Grasses, sedges, etc., as for other lakes, and in addition the following : 



1. Long-leaved reedgrass (Calamovilfa 



longifolia).* 



2. Big bulrush {Scirpus ocoidentalis) . 



Abundant on wet shore. 



3. Sedge (Oarex diandra).* Mature fruit. 



4. Mint (Mentha canadensis) .* 



5. Goldenrod (SoUdago altissima).* 



6. Groundsel (Senecio riddellii).* Flowers. 



SEMISUBMESGED PLANTS 



Dwninant: 



7. Big bulrush (Scirpus occidentaUs) . 

 Secondary species: 



8. Wapato (Sagittaria latifolia). Abun- 



dant. 



9. Reed (Phragmites communds). Abun- 



dant. 



10. Cord-grass (Spartina nvichauxiana) . 



11. Spike rush (EleocJiaris acuminata). 

 Abundant. 



12. Water smartweed (Polygonum amphi- 

 iium). 



Dominants: 



13. Sago pondweed (Potamogeton pectina- 



tus). 



14. Curly pondweed (Potamogeton per- 



foliatus richardsonii) . 

 Secondary species: 



15. Floating pondweed (Potamogeton na- 



tams). 



16. Illinois pondweed (Potamogeton illi- 



noensis). 



SUBMERGED PLANTS. 



17. Eelgrass pondweed (Potamogeton com^ 



pressus). 



18. Small pondweed (Potamogeton pusiU 



lus). Abundant. 



19. Bushy pondweed (Najas flexilis). 



20. Coontail (Ceratophylhim demersum). 



Common. 



21. Bladderwort (Vtricularia vulgaris). 



Common. 

 -. Algae abundant. 



FLOATING PLANTS. 

 22. Big duckweed (Spirodela polyrhiza). i 24. Star 



23. Small duckweed (Lemna minor). 



duckweed 

 Abundant. 



(Lemna trisulca). 



Wild-duck foods. — Plants in the above list which have considerable value 

 as food for wild ducks are: Nos. 2 (7), 8, 13, 18, 19, 20, 22, 23, and 24; those 

 of less importance are : Nos. 3, 10, 11, 12, 14, 15, 16, and 17 ; the remainder are of 

 no known value. ' 



