be especially useful in plantings that are being 

 grown as organically as possible, but they also 

 are suitable for use in conventional plantings. 



We encountered several problems in use of 

 these materials. 



1. They are malodorous, in particular the 

 herring hydrolysate (herring is an oily type of 

 fish) and the hydrolysate containing shrimp 

 waste. Also, in one instance the use of a hydro- 

 lysate attracted nocturnal wildlife that caused 

 damage to some adjacent plant material. 



2. The hydrolysates contain particles that 

 rapidly settle in the containers. (The shrimp 

 hydrolysate was especially coarse.) They had to 

 be constantly stirred to avoid settling during 

 application. These particles also clogged strain- 

 ers, and the materials could not be applied with 

 a watering can unless the perforated opening 

 was removed. Since uniform results were ob- 

 tained, however, these problems were only of 

 concern as a nuisance. 



Fish waste hydrolysates are available for 

 purchase from commercial suppliers. Gener- 

 ally, they are made up to contain about 2% N, 5% 

 P, and small amounts of other elements. Our 

 results indicate that they are usable for apples 

 and blueberries in the same manner as any 

 other fertilizer with a 2-5-0 analysis. Cost 

 comparisons should be based on price per 

 equivalent percent N. Our results suggest that 

 the other elements present in the hydrolysates 

 probably have little or no effect on perennial 

 plants. 



Hydrolysates are provided as liquid fertil- 

 izer. The problems we encountered with par- 

 ticulate matter will not occur when commercial 

 materials are used. All are filtered so that they 

 can be applied through irrigation systems. 

 These materials are being used extensively by 

 cranberry growers in Massachusetts, and they 

 appear to be fully suitable for use on other 

 perennial fruit crops. 



Fruit Notes, Summer, 1992 



19 



