Grower
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Grower
info
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The
most limiting factor for pear production in Saskatchewan is the cold
winters. Therefore, hardy varieties must be chosen for planting.
Hardiness
E - Extremely hardy, to -50oF or colder
David - E The fruit ripens in September. The skin is thin and the flesh is firm. This makes it good for cooking and processing. The tree is fire blight resistant.
Golden Spice - E The fruit ripens in October and is small(2 inches long). The skin is medium yellow lightly blushed with dull red. It is fair for fresh eating but very good for sauce and does not keep well. The tree is a good pollinator and somewhat fire blight resistant.
John - E The fruit ripens in late September and is unusually large for a prairie pear (3 inches long). The skin is greenish yellow blushed red with a cream-colored flesh that is juicy and aromatic. It is best harvested immature and then ripened off the tree but is even then only fair for cooking. The flavor is especially strong when the tree is grown on dry soil. The tree is a Pyrus ussuriensis/P. communis ussuriensis cross that is very hardy and fire blight resistant.
Ure - E The fruit ripens in September and is small (2 inches wide). The skin is greenish yellow with a flesh that is very sweet and juicy and is good for fresh eating and canning. The fruit will also keep for six weeks in refrigerated storage. This tree gives the best quality fresh fruit of the hardy selections. It also is naturally a semi-dwarf and is resistant to fire blight.
* The University of Saskatchewan is currently breeding for hardy cultivars and may be releasing one in the near future. This new cultivar is has some of the Asian pear in its parentage and looks like it will be the best hardy pear available, if it is released.
Like apples, most pears are not reliably self-pollinating. Almost any pear will pollinate any other, provided the two bloom at the same time. If the spring weather is ideal, which is rare in the north, almost any tree may self-pollinate. However, to ensure good pollination it is best to grow two compatible pears, as the bees will choose almost any flower over the pear blossoms because its nectar is low in sugar. Planting the trees approximately 20 feet apart will also increase the chances of pollination and, therefore, fruit set.
For more information go to: http://www.ento.vt.edu/Fruitfiles/VAFS-bees.html
Another consideration in pear choice is rootstock. Most nurseries will have already made the choice for you, but some will offer a selection. Pyrus ussuriensis offers a rootstock that is hardy, vigorous and resistant to fire blight, but is very susceptible to pear decline. 'Old Home' x 'Farmingdale' provides predictable vigor and tree size. Both of these rootstocks produces a "standard" or full sized tree.
Pears grow on a wide variety of soils provided they have sufficient moisture and are well drained. Like other fruits, they grow best on deep, fertile loams. A clay loam with a well-drained subsoil is generally considered best for them.
The orchard should allow for proper air drainage. A north or east facing slope will allow for and help to avoid early bud break (that a south slope would promote) and subsequent frost injury. It will also help to avoid the cold desiccating winds of the north and north west. To further reduce the winds a windbreak should be placed on the north and west edges on the orchard. Any protection (windbreak) that is placed on the slope side should be spaced to allow for air drainage.
There should also be a readily accessible supply of water for irrigation. If the orchard is located near of body of water it will also help to provide frost protection.
This should be done the year before planting. The goal is to remove as many weeds as possible, especially perennial weeds. Summer fallow woks good but it decreases the soil organic matter so a green manure crop should be used. This will add the needed organic matter and if a nitrogen fixing crop is used then nitrogen will also be added. In the fall, the soil should be worked to get a deep loose planting bed.
Pears should never be transplanted nor have their roots disturbed while leaves are on the tree. One-year-old plants are suggested as the best for planting. The generally recommended spacing for pears trees is 6-7 m apart in the row and 7-8 m between rows.
Yields are directly related to soil moisture, therefore, irrigation should be used for commercial production. During dry weather in the spring and summer the trees should be supplied with approximately one inch of water a week. Watering should not be done between August and October. This will allow for the tree to harden for the winter.
A light annual pruning of pear tree seems to be the most desirable procedure. Pruning should take place in late winter/early spring when the tree is still dormant. Interfering limbs, dead or broken branches and root sprouts should be pruned out. You should train and prune the young pear tree to the modified central-leader system. In this technique the tree is shaped to one tall trunk that extends upward through the tree, clearly emerging at the top. This shape makes a strong tree. It is also best to keep most cuts to the thinning-out type. Heavy pruning encourages the tree to produce succulent growth, which is both susceptible to fire blight and attractive to pear psylla. Pruning lightly every year will keep the fruit spurs and fruiting wood healthy and vigorous.
For more information on pruning your pear tree and instructions on how to prune to the modified central-leader system go to:
http://www.ces.ncsu.edu/depts/hort/hil/ag29.htm
http://tfpg.cas.psu.edu/pruning/slide1.htm
http://ohioline.osu.edu/hyg-fact/1000/1150.html
In pears, ripening takes place after harvest. Although pears can still ripen while still attached to the tree, the generally accepted commercial practice is to pick the fruit, by hand, before the onset of respiratory climacteric rise. This practice helps to increase the shelf life of the fruit during storage and transport. Most early-ripening pears do not have along storage life and break down quickly in cold storage. Late-maturing pears usually have a better storage life.
The best time for harvest is usually indicated by a slight change in color of the pears and by the stalk parting readily from the tree when the fruit is gently lifted. If the fruit is harvested too late, it will develop off-flavors and core breakdown, a postharvest physiological disorder. If harvested too early, they do not develop good eating quality and are more susceptible to scald, another postharvest physiological disorder. Harvesting pears at optimum maturity is important to ensure a high-quality product.
After the fruit has been gathered, it should be placed in a box or keg and stored in a cool room to ripen. If kept in a body together, where there is sufficient quantity, or kept from too rapid evaporation by being wrapped in paper, their flavor and size are fully preserved and, eventually, the fruit will acquire its full color and perfect maturity. Pears should be stored in a dark, cool room near freezing but no more than a degree or two below. If the pears are going into long-term storage, they need to be cooled down to storage temperature within 48 hours of harvest. This is usually done by a forced-air cooling method.
For more information go to:
http://www.msue.msu.edu/imp/mod03/01701543.html
http://eesc.orst.edu/agcomwebfile/edmat/html/fs/fs147/fs147.html
http://www.calpear.cam/rtl_ripe.htm
Fire blight - This is the greatest problem with pears, after hardiness. It is worse where the weather is wet less troublesome in dry climates and where it is too cold for pears to grow particularly well. The bacteria that cause fire blight enter through the blossoms, wounds or pruning cuts during the damp days of spring and work their way down through twigs and branches. Flowers and leaves near the tips suddenly wilt, turn brown or black and appear to have been scorched by fire. Blackened new growth is often curled at the tip. This is known as shepherd's crook. As soon as the diseased twig are noticed they should be pruned off at least 10 inches below the diseased area and the twigs should be burned. After each cut the pruning shears should be sterilized. Steps for protection can be taken by planting pears away from hawthorn and mountain ash, using trickle irrigation, avoiding heavy watering or fertilizing, and avoiding heavily pruning, especially just before flowering.
For more information: http://www.nysaes.cornell.edu/pp/extention/tfabp/firepm.shtml
Pear Scab - Pear scab is an economically important disease throughout the world and can cause serious losses on susceptible cultivars. It is sometimes called black spot. Symptoms of pear scab are very similar to apple scab. Lesions on leaves and petioles begin as round, brownish spots that eventually become velvety in appearance. Later in the season, small spots can be observed on the lower surface of the leaves. These are usually the result of late spring or early summer infections.
For more information: http://www.caf.wvu.edu/kearneysville/disease_descriptions/ompearsc.html
Pear Stony Pit - The causal agent of pear stony pit has not yet been isolated, but it can be transmitted by grafting. Symptoms begin as early as three weeks after petal fall, when dark green spots form on the fruit. Areas surrounding these spots continue to grow while spots stop, resulting in misshapen fruit with pits. Pits often become necrotic and the fruit beneath becomes gritty; heavily pitted fruit may become so gritty that it is difficult to cut with a knife.
For more information: http://www.caf.wvu.edu/kearneysville/disease_descriptions/omstnypt.html
For more information: http://www.nysaes.cornell.edu/pp/extention/tfabp/phyrstf.shtml
Fabraea Leaf Spot - Susceptible pear cultivars often are defoliated by midsummer, resulting in dwarfing of fruit and reduction of fruit buds. Leaf spot can be found on petioles, leaves, shoots and fruits. Initial lesions on leaves are tiny, round, purplish-black spots, which quickly enlarge and usually have a blackish-brown center. Spots grow together and severely infected leaves fall to the ground prematurely. Fruit lesions are larger than those on leaves and cause the fruit to crack and drop. Lesions on current season's shoots may be observed as small inconspicuous, purplish-black spots.
For more information: http://www.caf.wvu.edu/kearneysville/disease_descriptions/omfabrea.html
Pear Rust Mite - It occasionally causes injury to foliage and russetting of the fruit. The mites feed on the surface of the leaves and fruit, causing bronzing and russetting of the epidermal tissue. Bronzing occurs first on the undersides of the younger leaves near the midrib and then gradually extend outwards. After petal fall, more mites move from the foliage to the fruit where they first feed on the calyx end and cause localized russetting. If populations are allowed to increase feeding and russetting may spread over the whole surface of the fruit.
Pear Psylla
- This is
the most important insect pest of pear in all pear-growing regions. It
feeds on leaves but the resulting honeydew supports growth of sooty mold and
causes a black russet on fruit; necrotic areas on foliage may also
develop. The mite serves as the vector for the mycoplasma-like organism
causing pear decline when European scions are grown on Asian rootstocks, which
can be avoided by choice of rootstock/scion combination. Sooty mold and leaf
injury may reduce photosynthesis and return bloom.
Pearleaf Blister Mite - It is most often seen in neglected trees and causes blisters on the undersides of leaves, especially younger foliage, usually in a row along the midvein. The blisters are tiny green swellings at first, later expanding and turning red. These blisters eventually turn necrotic and brown. Small blisters may also occur on stems and around the fruit calyx and may cause fruit drop.
Pear Slug - While the larva of pear slug resembles a slug, it is actually a type of sawfly. Larvae feed only on pear foliage, causing a skeletonizing injury which leaves a thin area of brown tissue, often with a network of fine veins. If injury is severe, tree growth may be reduced in the following year.
For more pest information: http://www.caf.wvu.edu/kearneysville/wvufarm9b.html#PEAR
For information on physiological disorders go to: http://www.tfrl.ars.usda.gov/Disorders/peardisorders.html
For more information on postharvest diseases go to: http://www.tfrl.ars.usda.gov/Diseases/peardis.html
References
Bennett, Jennifer. The Harrowsmith book of fruit trees. Altona, Manitoba: Camden House Publishing, 1991.
Ferguson, Barbara J., Susan M. Lammers, Sally W. Smith. Ortho Books. San Francisco: Chevron Chemical Company, 1982.
http://www.sln.potsdam.ny.us/pears.html
Salunkhe, D. K., S. S. Kadam. Handbook of Fruit Science and Technology. New York: Marcel Dekker, Inc.
bee - http://www.kohala.net/bees/
pear drawing - http://www.sln.potsdam.ny.us/pears.html
water drop - http://www.scoutbase.org.uk/library/clipart/com/lg-gifs/wz-drop.gi
8 pears - http://www.usapears.com
