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In a raspberry planting the problem is not one of shading out of the plants 

 since it is seldom that weeds are taller than the raspberries unless the raspberry 

 plants are very weak, but rather one of root competition. Since the raspberry 

 plant is very shallow rooted, the roots of weeds, and particularly grasses, com- 

 pete directly for water and nutrients. Therefore, when a raspberry planting 

 becomes very weedy, raspberry plants lose vigor rather rapidly. 



Blueberries and grapes tolerate weeds much better than strawberries or rasp- 

 berries. Grapes will grow and produce under a sod culture as evidenced by the 

 fact that many a grapevine has grown and borne for years in a backyard lawi. In 

 commercial vineyards, grapes are always cultivated because eliminating weed 

 competition results in so much higher yields. Cultivated blueberries, after they 

 become established, tolerate weeds as well or better than any of the other small 

 fruit crops. Many of the commercial blueberry plantings in the state are handled 

 under sod culture. Nevertheless, the blueberry will grow and produce much better 

 if weed competition is removed. The blueberry bush is shallow-rooted and, there- 

 fore, as with the raspberry, there is direct competition between the roots of 

 weeds and the roots of the blueberries. By actual chemical analysis it has been 

 shown that there is more nitrogen in the leaves of blueberry plants gro\im in a plot 

 where weeds were chemically eliminated than in the leaves of plants grown in a 

 very weedy plot, A darker green color of the leaves of plants x^ithout v/eed 

 competition, as compared with the yellowish green of leaves on wecdj' plots, gave 

 visual signs of this difference. 



Since weed couipetition in small fruit plantings is undesirable, what is the 

 best and most economical method for reducing to a tolerable minimum or eliminating 

 this competition? This is not an easy question to answer. Grox^ers differ in the 

 amount of weed competition which they consider tolerable. There are many ways of 

 going about the problem of weed control. 



Let's take a look at the tolerable minimum of weed competition. Among 

 strawberry growers there are those who consider that weed control is adequate if 

 they cultivate a few times in the spring and early summer until runners begin to 

 interfere. Then in late summer and fall the tops of the weeds are mowed off 

 above the strawberries. The bed is then mowed again before picking the next 

 spring. Although the yields are not as high, the labor bill is much lower. 

 Therefore, the grower feels that the method is satisfactory. At the other ex- 

 treme are those grov^ers who use a hill or spaced row systera and weed their beds 

 regularly so that weed competition is reduced to a very low order. The tolerable 

 minimum in most beds probably lies betv/een these extremes. 



In regard to cultivated blueberries, the situation is quite different. In 

 many of the plantings the bushes were set too close so that when the bushes 

 matured there was not enough space left for mechanical cultivation, and since hand 

 work is too costly a sod has developed in many blueberry fields. On the other 

 hand, in the newer plantings where the bushes have been set sufficiently far apart, 

 the fields arc kept relatively free of weeds by cultivation. 



The methods of v/eed control can be grouped under three major headings: 

 (1) cultivation, (2) mulching, and (3) chemicals. Under each of those general 

 headings one will find numerous variations and not infrequently the methods of 

 two or all three of these groups may be combined. For example, a raspberry or 



