18 THE MONTANA EXPERIMENT STATION. 



2. Summer Fallow. — Where it is desired to grow a grain 

 crop as continuously as possible, it is hardly profitable to seed 

 down in timothy, alfalfa or clover for a single year, and, as exten- 

 sive cultivated crops, such as are grown in the Mississippi valley, 

 are not here feasible for the reasons stated, in many parts of the 

 state a system of summer fallow has been adopted, which consists 

 usually in plowing under the weeds late in May or June before they 

 have matured and then going over the soil once or twice 

 afterwards with a disk or cultivator to prevent the new growth 

 attaining any size. This effectually reduces the growth of the 

 annual weeds so troublesome to grains and materially increases 

 the fertility of the soil, but the loss of income from the fallowed 

 land and the expense of cultivation, far offset any advantages 

 thus derived, while, unless the land is disked after plowing, it is 

 often worse seeded in weeds than before. It is much more profita- 

 ble either to seed down foul wheat lands in some hay crop or in 

 grain suitable for pasturage and thus secure some return from the 

 land while the weeds are being killed. 



3. Pasturage. There are some weeds like the sunflower, 

 wild oats, and wild mustard, which are very difficult to clear out 

 of land, when once they have a good foothold. For such weeds, 

 and other of like nature, a very effective and profitable method of 

 eradication is to sow the land down in some grain suitable for 

 pasturage, such as rye or oats, or in clover or mixed grains, and 

 to keep this closely cropped by sheep, so that no weeds that come 

 up will have any chance to mature seed. Two or three years of suc- 

 cessive pasturage in this manner should effectually clean the worst 

 infested lands. Other kinds of stock will do, but they are more 

 prone to .exercise selection and permit the growth of the less 

 edible varieties. Sheep clean off all alike. 



4. Special Methods. — In some cases special methods may be 

 employed with advantage. Hand-pulling is frequently possible in 

 small fields or patches of grain infested with the sunflower, wild 

 mustard, tumbling mustard, etc. This may be done by boys 

 under competent supervision, and is best undertaken when the 

 weeds first come well into bloom and before they have matured 

 any seed. The bright yellow flowers serve as guides to the loca- 

 tion of each individual and their absence clearly marks the strip 



