Chemical weed control. Paraquat can be applied anytime 

 during the growing season under newly planted trees and 

 dichlobenil is safely applied in the late fall or early winter 

 at the end of the growing season. Apply paraquat at the rate 

 of 1 quart plus spreader per acre in mid-May and again in 

 mid-July taking necessary precaution against hitting the tree 

 with the direct spray or spray drift. Drift can be a major 

 problem when applying herbicide sprays. To reduce this 

 problem, you can use a foaming agent (adjuvant) with the 

 spray, avoid spraying when the wind is greater than 5 miles 

 per hour, avoid high pressures, and use nozzles that produce 

 coarse sprays with a minimum of fine droplets. A flooding 

 flat nozzle is particularly good for drift control and is de- 

 signed to operate at 15 to 20 psi. 



Dichlobenil (Casoron*) should be applied at the rate of 

 100 to 150 pounds of 4% granular per acre. Its use is de- 

 scribed elsewhere in this publication. 



Guards for mouse protection. Encirclement of tree bases 

 with hardware cloth guards to prevent mouse injury has been 

 a standard practice for many years. Hardware cloth must 

 have 3 or 4 wires to the inch to be mouse-proof. The guards 

 should be 6 inches in diameter and 18 inches in height. They 

 should be set in the ground on top of the tree's root crown. 

 Hardware cloth is expensive and has to be cut to the desired 

 dimensions. 



Plastic-lined mouse guards can be purchased precut from 

 a local distributor. They are cut to form a circle 3 inches in 

 diameter and 18 inches in height or a 6 inch circle with 10 

 inch height. 



Plastic mouse guards have become popular the last several 

 years because they are more economical than hardware cloth 

 or plastic-lined mouse guards. However, they shelter insects 

 and should be examined annually for constriction of trunk 

 growth. 



Pruning 



At this point, it is well to recognize the fact that pruning 

 procedures cannot be fully and accurately described. Fur- 

 thermore, no two trees, which appear similar at planting 

 time, grow alike even when subjected to similar pruning and 

 training procedures. Cultivars differ in growth characteristics 

 and their response to pruning. Lastly, rootstocks, soil and 

 growing conditions influence tree vigor and pruning and 

 training requirements of trees. At best, all we can do is dis- 

 cuss the basic principles for training and pruning and you 

 will have to learn the finer details by experience. 



We suggest training and pruning trees to obtain and main- 

 tain a conical shape (Christmas tree shape) because this 

 form allows better penetration of sunlight into the trees 

 and light distribution along the sides of trees. A conical tree 

 shape is only possible with a central leader tree and only 

 possible by removing and/or shortening the strong branches 

 in the upper part of the tree and retaining the shorter, weaker 

 branches. Presently, many trees in our orchards have large 

 branches in the upper third of the trees which inhibit light 



penetration into the lower section of the trees. 



In the past, the main objective of pruning an apple tree 

 was to produce a large percentage of Extra Fancy apples at 

 lower costs. This is still the prime objective but many growers 

 are now attempting to obtain the benefits of early, heavy 

 production by closer spacings of compact trees. As a result, 

 the problem has arisen of trying to contain the trees within 

 their allotted spacings especially when thecultivar-rootstock- 

 soil has not been properly matched. 



Training and pruning of trees becomes increasingly impor- 

 tant as planting density increases. Growers lacking time to 

 do detailed pruning and training, as being suggested for medi- 

 um and high density plantings, would do well to establish 

 only low density plantings. Such a planting system is rela- 

 tively easy to manage and not so sensitive to variations in 

 soil conditions, errors in pruning, and other management 



procedures as are medium and high density plantings 



7 



Season to prune. Commercial growers commence pruning 

 some types of fruit trees in January, but home orchardists, 

 because of limited tree numbers, can wait until the arrival 

 of milder weather. Pruning may be done through the blos- 

 soming period but late March or April is preferred. Water 

 sprouts on apple trees should be removed in mid-summer 

 and dead or diseased branches can be removed whenever 

 they are present. 



Pruning systems. It appears logical to suggest the following 

 pruning systems, based on orchard density, for Massachusetts 

 orchards. 



1. Low density orchards: minimal containment of tree 

 spread and height. 



2. Low density orchards: containment of tree height. 



3. Medium density orchards: containment of tree spread 

 and height. 



4. High density orchards: staked ortrellised. 



Pruning low-density orchards with minimal containment of 

 tree spread and height This system involves pruning tech- 

 niques used in the past and described in countless pruning 

 bulletins. The tree has a central leader and pruning involves: 

 (1) the selection of desirable scaffold limbs; (2) the removal 

 of undesirable limbs to eliminate whorls of branches and 

 thus permitting only one branch to develop at a given level 

 as shown in Fig. 10A; (3) maintaining the dominance of the 

 leader by suppressing or removal of competing leaders; 

 (4) restricting too rapid development of certain scaffold 

 limbs by heading-back to an outward growing horizontal 

 shoot or branch; and (5) on bearing trees, the elimination 



^Growers may be able to increase production per man hour 

 and per acre without the problems encountered with vigor- 

 ous cultivars on semi-dwarf rootstocks at close spacings if 

 M.26 and interstem trees prove reliable under our con- 

 ditions. 



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