218 



THE MONTHLY BULLETIN. 



Such measures of control arc, however, a new departure in California, 

 and there is abundant room for demonstrations! work to convince the 

 farmer of the value of the weed control methods used in other states. 

 The time has come when we should give less thought to extensive and 

 more to intensive farming. With crops selling at the extraordinary 

 prices they bring at present, with land values increasing and a shortage 

 of certain crops, it is not only right but profitable for the farmer to 

 investigate every means which will increase his production. 



Chemicals. 



The chemical spray must commonly used in the East is a solution of 

 iron sulphate. .Many different chemicals were tried out with varying 



results. The iron sulphate in 

 every instance proved the most 

 satisfactory. The usual strength 

 of the solution is two to one, i. e., 

 100 pounds of iron sulphate to 50 

 gallons of water. This should be 

 applied to the growing weeds 

 when they are about six inches 

 high. A spray pump capable of 

 maintaining at least 150 pounds 

 pressure should be used, with a 

 set of nozzles arranged in a hori- 

 zontal boom 6 to 12 feet long. 

 The nozzles should be set nearly 

 vertical and about 12 to 18 inches 

 apart. The spray should be med- 

 ium fine and penetrating. Fifty 

 gallons should cover one acre. 



This spray will do very little 

 damage to the growing grain be- 

 cause the growing point of the 

 grain plant is protected by a 

 sheath of leaves. The broad- 

 leaved mustard is, however, easily 

 destroyed by the poisonous iron 

 sulphate and soon withers to noth- 

 ing, leaving the space it occupied 

 In be filled by grain, thus increas- 

 ing the yield. 



Time to Spray. 



The mustard should be sprayed 

 when it is about six inches high, 

 and growing rapidly. The spraying in the experiment herein recorded 

 was done on a bright, sunshiny day, followed by two days of the same 

 kind of weather. A rain just after spraying is apt to wash so much of 

 the material off that it will have to be reapplied. Better results will also 

 be obtained on a still day than on a windy one. because the weeds and 

 grain will be erect and the spray can penetrate to the lower portions 

 of I he plant with less difficulty. 



Fig. 4 7. — Wild mustard, Brassica arvensis 

 L... commonly called "Charlock," a weed 

 of very persistent character and rapid 

 growth. It is not quite as common as 

 Brassica campestris but is rapidly spread- 

 ing. U develops later in the season than 

 the common yellow mustard and as a 

 result takes the moisture from the crop 

 just when it is most needed. (Courtesy 

 of "Farm Weeds.") 



