4 BULLETIN 720^ U. S. DEPARTMENT OF AGKICULTTJBE. 



SEDGES (21.62 PER CENt). 



Practically all the sedges contribute to the diet of the mallard. 

 Their fruits, or akenes (the seeds with their immediately investing 

 coats), are of most importance, although the stems, leaves, root- 

 stocks, and tubers also are eaten. Seeds or other parts of bulrushes 

 were found in the greatest number of stomachs. Unidentified bul- 

 rush seeds occurred in 540 gizzards, from 400 to 1,200 in some. The 

 akenes of river bulrush {Scirpus jluviatilis) were identified in 45 

 stomachs, and those of Scirpus cuhensis in 286. No -fewer than 

 28,160 akenes of the latter species were obtained from the crop and 

 gizzard of a single mallard. Akenes of sedges of the genus Fim- 

 hristylis occurred in 279 stomachs, the largest number in any one 

 being 1,000. Eighty-seven hundred seeds of a Cyperus were taken 

 from a single gizzard; tubers of these sedges also were found. Saw 

 grass (Cladium) is rather important among the sedges fed upon by 

 the maUard, and its seeds were identified in 246 stomachs, 1,100 

 being the largest number found. 



GRASSES (13.39 PER CENT). 



Wild rice (Zizania aquatica) is the most important of the grasses 

 fed upon by the mallard. The value of this plant as a duck food is 

 not exaggerated in popular opinion, and it is unfortunate that the 

 plant is almost as erratic and disappointing in its responses to 

 attempts at propagation as it is valuable as a duck food in the 

 places it chooses to grow. Wild rice was found in 91 of the stomachs 

 examined for this report, and no fewer than 1,200 to 2,400 kernels 

 had been devoured by single birds. The kernels are sometimes 

 taken in sprouting condition, and the leaves of the plant occasionally 

 are eaten. 



Among the more important of other wild grasses represented in the 

 diet are: Wild millet (EdiinocJiloa crus-galli), switch and crab grasses 

 (Panicum), rice cut grass (Homalocenchrus) , salt-marsh grass (Spar- 

 tina), and white marsh or cut grass (Zizaniopsis) . 



Grain, which is largely produced by plants of the grass family, 

 may best be considered in the present connection. Oats, corn, 

 barley, wheat, buckwheat, and rice were found and together consti- 

 tute 2.99 per cent of the total food. Rice only was certainly gleaned by 

 the birds from cultivated fields and all of it was waste. Mallards 

 eagerly feed on rice in the shock when opportunity occurs. Thus in 

 1917, when various factors delayed harvesting until the arrival of 

 wild ducks from the north, mallards destroyed about $35,000 worth 

 of rice in the vicinity of De Witt and Stuttgart, Ark. Probably 

 all the other grains found in the stomachs of the birds examined 

 were put out as bait for the birds. This is not to say that mal- 

 lards do not feed in grain fields, for they are well known to do so. 



