168 



STATE BOARD OF AGRICULTURE. 



out of rolls of building-paper by a special hand tool and hammer. It 

 really costs less than one would expect to treat an entire field, and 

 succeeds in restricting the invasion of the maggots to a large extent. 



We have succeeded in restricting their ravages materially by placing 

 about a tablespoonful of tobacco dust about the stem of each plant, and 

 this is common practice among ^ome of our Michigan market gardeners, 

 although the paper pads probably are more effective. 



Professor Cook, formerly of this station, and afterward Professor 

 Slingerland obtained quite satisfactory results with an emulsion of 

 crude carbolic acid. Make it according to the formula on page 66, and 

 dilute about thirty times with water. This should be applied about 

 the base of the plant the day after setting and repeated every ten days 

 until about May 25th, using about one-half teacupful to each plant and 

 pouring it about the root with a sprinkler. 



Fig. 17. — Spraying cabbage, with knapsack pump and short extension. Original. 

 INSECTS AFFECTING THE LEAVES. 

 The Cabbage Aphis (ApJiis hrassicae). 



From mid-summer until fall, cabbages are subject to attack by plant- 

 lice. Of course the lice are present earlier in the season but in such 

 small numbers that they escape detection. Both winged and wingless 



