WASHING WATERING 237 



usually results in making a tree more vigorous. One reason 

 is that it destroys insects and fungi which lodge underneath 

 the bark; but probably the chief reason is that it softens the 

 bark and allows the trunk to expand. It is possible, also, 

 that the potash from the soap or lye eventually passes into 

 the ground and affords some plant- food. Trees are ordi- 

 narily Washed with soap suds or with a lye solution. The 

 material is usually applied with an old broom or a stiff 

 brush. The scrubbing of the tree is perhaps nearly or quite 

 as beneficial as the application of the wash itself. 



It is customary to wash trees late in spring or early in 

 summer, and again in the fall, with the idea that such Wash- 

 ing destroys the eggs and the young of borers. It no doubt 

 will destroy borers if they are just getting a start, but it will 

 not keep away the insects which lay the eggs, and will not 

 destroy the borers which have found their way underneath 

 the bark. It is perhaps quite as well to wash the trees very 

 early in the spring, when they are starting into growth. It 

 is an old practice to wash trees with strong lye when they 

 are affected with the oyster- shell bark louse. The modern 

 method of treating these pests, however, is to spray with 

 some kerosene compound when the young growth is starting, 

 for at that time the young insects are migrating to the new 

 wood and they are very easily destroyed. 



Watering House Plants. It is impossible to 

 give rules for the Watering of plants. Conditions that hold 

 with one grower are different from those of another. Advice 

 must be general. Give one good Watering at the time of 

 potting, after which no water should be given until the plants 

 really need it. If, on tapping the pot, it gives out a clear 

 ring, it is an indication that water is needed. In the case of 

 a soft-wooded plant, just before the leaves begin to show 

 signs of wilt, is the time for Watering. When plants are 

 taken up from the ground, or when plants have their roots 

 cut back in repotting, gardeners rely, after the first copious 

 Watering, on syringing the tops of the plants two or three 



