Figure 21. — Several muskrar runs leading to the dwelling house were exposed when 

 this "three-square" marsh in Louisiana was burned. 



Marshes on the xVtlantic coast are 

 burned about the middle or the 

 latter part of February. To burn 

 in early fall would mean little cover 

 for the muskrats until late spring. 

 In the Gulf Coast marshes three- 

 square is burned between October 

 10 and January 1 when the water is 

 only a few inches deep (fig. 21). 

 This helps maintain a supply of 

 three-square bulrush, a favored 

 food of the muskrats. 



The beneficial effects of marsh 

 burning appear to outw^eigh any un- 

 favorable ones. Burning opera- 

 tions indirectly control insects that 

 attack many of the favorite food 

 plants of the muskrat, such as the 

 widely distributed and very injuri- 

 ous lepidopterous stem borer of cat- 

 tail {Arazama obUqua) and several 

 leaf miners on three-square bulrush 

 that often prevent normal seed set- 

 ting over large areas. Productive 



muskrat marsh should never be 

 burned during an abnormally dry 

 spell, as root burns occur then, seri- 

 ously altering the marsh structure 

 and killing desirable vegetation. 

 Deep burns can be used effectively 

 in breaking up dense stands of the 

 less desirable Spartina patens. 

 During very dry periods, marsh 

 fires result in the death of many 

 rabbits and raccoons, and occasion- 

 ally muskrats, minks, and otters. 

 If there is some water on the marsh 

 at the time of the fire the loss is gen- 

 erally slight. Fortunately, inhabi- 

 tated muskrat houses are rather 

 moist and chinkei with mud, and do 

 not burn readily ; the only damage 

 to them is a slight blackening and 

 scorching of their tops. 



Generally speaking, cattle and 

 muskrats do not go well together. 

 Cattle trample the muskrat houses 

 and runw^ays and frequently dam- 



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