Fertilizing and Watering Trees 2 1 



difficult to wet and slow todi \ out. liiev recjiiirc more water 

 per application and applications at less frecjiient intervals 

 than do sandy soils. Sandy or light soils are easy to wet but 

 must be watered more frecjuently than heavier soils bee ause 

 their water-holding capacity is less. 



The most satisfactory means of supplying and uniformly 

 distributing adequate water to an established tree is with a 

 garden hose and an oscillating lawn sprinkler. To wet the 

 soil thoroughly requires the equivalerU of 2 inches of rainfall. 

 During prolonged dry periods in the summer, watering 

 should be repeated at intervals of 2-3 weeks. Coffee cans 

 placed near the sprinkler make handy gauges for measuring 

 the amount of water that has been applied. If water begins 

 to run off the surface before the intended amount has been 

 supplied, half of the volume should be applied one day and 

 the remainder the following day. 



Other means of supplying supplemental water are soaker 

 hoses and root-watering needles. Soaker hoses are suited for 

 such limited areas as border, hedge, and foundation plant- 

 ings. A root-watering needle is conveniently used around 

 small trees or shrubs. The needle has the advantage of 

 injecting water into the immediate area of the roots; 

 however, since only a limited amount of soil is watered at 

 each injection, the needle must be moved at frequent 

 intervals. 



Summary of recommendations 



Recommendations for the fertilization of shade trees and 

 shrubs should be based on controlled experiments using 

 known plant species and known soil types; however, only a 

 limited number of such studies have been made. These 

 recommendations, therefore, are baseci primarily on 

 experiments by the authors and on information gleaned 

 from research in arboriculture, pomology, forestry, and 

 agronomy. 



