WEEDS OF MONTANA. 



A great part of the weeds of the grain fields, besides providing 

 for independent distribution, ripen their seeds at the same time as 

 the cultivated grains and depend upon the farmer to exercise like 

 care in planting them again. Hence it is necessary, if these weeds 

 be kept out of our fields, that all seed sown be first carefully win- 

 nowed, and thus the farmer may later be saved much labor and 

 expense in their extermination, or in the reduced yield from the 

 grain planted. The cockle, sunflower, wild oat, and wild mustard 

 are largely distributed in the seed planted and these are counted 

 among the worst weeds in the state. Garden and lawn seeds are 

 notoriously contaminated and the most troublesome weeds of the 

 East are thus imported, particularly the dandelion, plantain, chick- 

 weed, sow-thistle, ragweed, Canada thistle and many others 

 equally troublesome. 



ORIGIN OF OUR WEED FLORA. 



Some plants in every country acquire the weed habit by 

 adaptation to meet certain conditions, which have resulted in the 

 destruction of the normal vegetation over areas more or less 

 extensive and of fair permanence. Under natural conditions such 

 denuded soil is found in cases of forest fires, landslides and floods. 

 The first two are of infrequent occurrence and the areas effected are 

 soon re-covered, mainly with wind-disseminated species. The 

 floods resulting from melting snows and spring rains are fairly 

 regular in time and permanent in place, so the alluvium deposited 

 each season affords a fertile and permanent ground for the growth 

 and reproduction of the seeds transported in the water. It is 

 these native alluvial weeds, of which the annual sunflower and the 

 horse weed (Iva) are examples, that spread so readily to our fields 

 and gardens with the water used in irrigation and there become 

 permanent pests. 



To an appreciable extent, too, weed conditions are afforded by 

 the soil excavated about ant hills, gopher burrows and prairie-dog 

 towns, and here flourish in abundance such species as Krinitzkia 

 crassisepala, Echinospermum Redowskii, Plantago Patagonica, 

 Malvastrum coccineum and Cleome integrifolia, which now find 

 themselves equally well adapted for growth in yards, streets and 

 waste places. But man in his various pastoral, agricultural and 



