Winter apple trees

Phenolic compounds may be involved in plant responses to cold stress and in plant acclimation to low temperature. Acclimation of apple trees to cold climates was found to be associated with a seasonal accumulation of chlorogenic acid [102]. Strengthened frost tolerance in a variety of plants were attributed to thicker cell-wall lignification or suberization [102]. Thickening of cell walls and increased production of suberin-type lipids were observed in cold-acclimated winter rye leaves [103]. The presence of suberin in cell walls may favour membrane cell-wall adhesion, a major factor in the resistance of plant cells to freezing [104]. 

For optimum fruit quality, almost all pear varieties need a warm site, rather similar to that required for wine grapes. If these conditions are not present, the fruit very often does not have the desired melting texture and has little flavour in extreme cases the fruit may taste carroty . This applies particularly to late-ripening cultivars. Pear trees are somewhat more sensitive to winter frost than apple trees, and are at severe risk from late frosts because flowering is about 10 days earlier. 

In the autumn, winged sexual forms develop. These return to the apple tree if they have not remained there all the time. The fertilized females then lay their winter eggs. 

The apple grass aphid hatches from the winter eggs as soon as the huds open. The nymphs suck on the rosette leaves or flower buds. At the beginning to middle of May they migrate to weeds (preferring annual meadow grass). The infestation then decreases abruptly. In autumn they return to the apple tree, where they copulate and the females lay the winter eggs on the old wood. 

DIRECT. After the damage threshold is exceeded, a pyrethrum-rotenone spray should be applied at temperatures above 12°C. If very early treatment is necessary because of the high population density, a second spraying may sometimes be needed, as beetles move continuously from the winter hiding-places to the apple trees until the eggs are laid. 

Prevention is the best control. Rust diseases thrive in moist conditions, so anything you can do to promote leaf drying will limit disease problems. Plant apple trees only if cedars are at least 4 miles away this will reduce the chances of the disease spreading. If you want to grow both cedars and apple trees, plant rust-resistant species or cultivars of both plants. Prune off and destroy galls before late winter. 

Even at small concentrations fenarimol has a protective, curative and eradicant effect against powdery mildew fungi of apple trees, vine, Cucurbitae and roses. It gives also efficient protection against Typhula incarnata fungi causing snow mould in winter barley (Ebenebe and Fehrmann, 1976). 

Like all fruit trees, apples need to be pruned annually for best results. Once established, all tree forms benefit from winter pruning. Trained forms—cordons, espaliers, and fans—need extra pruning in summer to keep their shape. Pruning aims to achieve a number of objectives ... 

Apple problems Aphids like to colonize tender shoot tips if they go unnoticed, it may become neoessary to prune out badly infested and distorted growth near right). A proteotive band far right) used to prevent wingless female winter moths from olimbing trees to lay their eggs, may also help with aphid problems—by keeping ants, which farm aphids, out of the tree. 

Pick up fallen fruitlets, as these may house sawfly larvae. Earwigs may be found on fruits, but do not cause significant damage, and should be tolerated as they are excellent apple pest predators. In fall, remove mulches and rake up all fallen leaves, or mow over them so that they are taken down into the soil quickly, as they may harbor scab spores that could reinfect the tree in spring. Apply grease bands to trees and stakes to deter winter moths keep in place until early spring. After harvest, remove all unpicked fruits from the tree, and hang up fat to attract birds, which eat pests. 

The fact that so many old pear cultivars bear French names shows how valued the pear was in France the long season and warm conditions of the Continent suit them well. Pears are more difficult to store than apples, but cultivars are available to span a season from midsummer through to winter without special storage conditions. Flardy in Zones 4-9, pears are quite long-lived trees, but the quality and size of fruit starts to decline after 30 or 40 years. 

From the fourth year onward, pears are pruned as for apples (see pp.297-298) all benefit from routine pruning in winter, and wall-trained trees need additional pruning in summer. Spur-pruning will enhance cropping. 

What to do Grow resistant cultivars. Mulch under trees to stop soil from drying out Water trees in dry weather. In winter, cut out infected shoots. In spring, remove infected leaves and shoots. Spray with seaweed extract to promote strong growth. Fungicide spray Sulfur, although it can harm some apples. Check the label before use. 

EMERALD OF THE PHILOSOPHERS — A name which has been given to the Flos Coeli, and sometimes to the Dew of May and of September. The last is looked upon as masculine because it is more cocted and digested by the warmth of the summer. The other is considered female because it is colder, cruder, and more akin to winter in its quality. Some chemists, understanding these words literally, have imagined that dew was the matter from which the Philosophers extracted their mercury, because they often say in their books that mercury is male and female. So they have deemed that the union of the Dew of May with that of September would constitute that marriage so recommended by true chemists. But they should have noticed that the matter of their mercury must be mineral because the ox will produce but the ox, the apple an apple only, and it is an egregious blunder to suppose that any metal can ever be produced from a tree or a plant. 

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