ORNAMENTAL AND SHADE TREES 



487 



ADVICE FOR AUGUST 



1. Commence pruning shade and ornamental trees this 3. Collect and burn egg masses of the Tussock moth 

 month. and similar insects. 



2. Transplant evergreens after the 15th of August. 4. Collect and burn cocoons of the bog worm and 



similar insects. 



QUESTIONS AND ANSWERS 



Q. Please give me the proper soil elements necessary for 

 vigorous growth of maple, elm, oriental plane, catalpa, poplar, 

 locust, beech and birch, also fruit trees. Present soil is clay and 

 gravel. Are wood-ashes and bone-dust and lime advisable? 



W. M. C, Oaktnont, Pa. 



A. Replying to your inquiry, the trees you mention will grow 

 in any ordinary good farm soil. The elm, beech and fruit trees 

 are more fastidious in their soil requirements, and need more 

 moisture than others mentioned. The plane will adapt itself to 

 the ordinary poor soil of the city street and the catalpa and 

 locust will grow in the dry, poor soil. The poplar is the least 

 particular o c all and will grow where little else will grow. The 

 addition of bone-dust and wood-ashes is very good, but the lime 

 is more of a local question, depending on sourness, etc., of soil, 

 though a little of it is likely to do good. The best fertilizer that 

 we would recommend for your soil would be well rotted manure 

 dug in thickly. 



Q. Is it advisable to remove the extra growth developing in 

 bunches of twigs and leaves on the main branches of elms or 

 oaks? Shall appreciate your advice. 



E. L. S., Cincinnati, Ohio. 



A. The extra growth on the elms and oaks should not be cut 

 off. The vast amount of rain this season in the East has produced 

 a profusion of growth which does the trees good and makes them 

 more attractive. To keep the crown thick with foliage is a good 

 policy for the upkeep of shade trees. 



Q. There is a growth or gall similar to the one enclosed on 

 my hickory trees, and I write to see if you can assist me with a 

 cure for the same. The growth is rather round, comes on the 

 young shoots, and in time comes on every shoot so that it stops 

 all growth and the trees die. Some of the largest hickory trees 

 around here are giving up the fight. I enclose a leaf of hickory 

 which ought to be helped by the right spray. The growth is same 

 color as shoot and opens up as specimen of its own accord. 



N. W. C, Eden, N. Y. 



A. Replying to your inquiry, I beg to say that your hickory 

 is affected with what is known as the hickory gall aphid, a species 

 somewhat common and one which occasionally seriously dis- 

 figures hickory trees and at such times causes considerable 

 injury. The remedy consists in spraying with lime-sulphur wash 

 in the early spring, and cutting and burning the galls in early 

 summer before the plant-lice have deserted them. The latter 

 method, however, is sometimes very difficult to carry out on ac- 

 count of the large size of the trees. These methods would apply 

 to lawn and shade trees but would not be practical for checking 

 the insect in forest trees. 



Q. Please prescribe proper treatment for elm too large to 

 spray conveniently; leaves badly eaten and shrivelled up. Is 

 nicotine spray advisable for maple gall ? 



W. M. B. C, Oakmont, Pa. 



A. Relative to your large elm, the eating of the leaves is very 

 likely due to the elm-leaf beetle. Spraying with arsenate of lead 

 in early June is best for it. The grubs of the beetle, however, have 

 a habit of crawling down the trunk to the base of the tree in 

 early August to pupate, and while the insect is in that pupa stage 

 you can collect them at the base of the tree and destroy them. 

 The curling of the leaves is probably due to plant-lice which 



appear on the under side of the leaves. Spraying with whale-oil 

 soap, one pound to ten gallons of water, is the best method of 

 fighting this insect. Nicotine spray for maple gall, if the tree is 

 large, is too expensive and therefore never used. Use lime- 

 sulphur wash in early spring in place of the nicotine. 



Q. I want information in regard to the proper treatment of 

 soil in seed beds to eliminate the growth of weeds. 



Can the soil be inoculated with a formula that will destroy 

 weed seeds and not injure the tree seeds? Is there any spraying 

 mixture that could be used after weeds had started to grow that 

 would kill the weeds and not injure the little seedlings? 



Any information you can give me on this subject will be 

 appreciated. 



D. H., Dundee, III. 



A. Replying to your inquiry I will answer the questions in the 

 order in which they are put. 



1. There is nothing that can be put into the seed bed that 

 will keep out weeds, and will not at the same time prevent other 

 vegetation from growing. 



The growth of the weeds can be prevented, however, by the 

 following methods : 



(a) The bed may be started a year previous and allowed to 

 remain without any seeding for the whole summer, and during 

 that summer it should be cultivated frequently in order to kill 

 off all weeds. This is often done, and it is known as " summer 

 cultivation " as a preparation for future planting. 



(6) Another method may consist of something which is often 

 used by rose growers ; namely, to sterilize the soil by the method 

 of steaming. I have heard of cases where this steaming process 

 is applied to outside beds, as well as to heaps of soil within green- 

 houses. A modification of this method may consist of burning 

 the vegetation in heaps along the bed all through the summer, 

 and in that way producing a weedless bed for the following year. 

 2. There are a number of mixtures that can be used to destroy 

 weeds, but would not be applicable to beds where seedlings are 

 growing, because they would destroy every other form of vegeta- 

 tion at the same time. 



Q. The tops of my beech and birch trees are dying off in large 

 numbers. Please tell me the cause of the trouble and what to do. 



L. M. C, Reading, Pa. 



A. Very likely your beeches are suffering from impoverished 

 -soil, insufficiency of moisture or late developing winter injury. 

 We have had complaints from many parts of the East where the 

 beeches were going back the same way. In most of these cases it 

 was not an insect or disease that was responsible, but rather a 

 climatic or soil stress of one kind or another, and where we had 

 a chance to apply a remedy we found that special stimulation 

 of manure, water, cutting back the crown and even artificial 

 fertilizer have helped very much. 



The birch trees are very likely affected by the bronze birch 

 borer, an insect which has done a great deal of damage of late 

 years to all species of birch trees. Removing the infested tops 

 and burning them before the grubs have a chance to go too far 

 down is the most practical remedy. 



Q. What do you consider the best vine for covering banks? 



R. P. R., Hartford. Conn. 

 A. If the spot has plenty of sun, use Rosa zinchnriana. If it 

 is more or less shaded, you might use Hall's honeysuckle. 



