Manzana

Clemson HGIC, 'Fire Blight of Fruit Trees', hgic.clemson.edu/factsheet/fire-blight-of-fruit-trees (fetched in-container 2026-09-02; read by the maintainer 2026-09-02): 'Fire blight can be very destructive to apple and pear trees. Pear trees are particularly susceptible' (crabapple and quince named as well); 'Both rainfall and insects (such as bees, ants, flies, aphids, and beetles) that are attracted to the bacterial ooze spread can spread fire blight'; 'Avoid excess nitrogen fertilization, which results in excess succulent growth, because if injured, succulent new growth is easily infected'; 'Pruning cuts of twigs and branches are made a minimum of 8 to 12 inches below any sign of infected tissue'; resistant apples 'Empire', 'Enterprise', 'Freedom', 'Gold Rush', 'Honey Crisp', 'Liberty'; pears 'Keiffer', 'LeConte', 'Moonglow', 'Orient'.

UNH Extension, 'Fire Blight' fact sheet, extension.unh.edu/resource/fire-blight-fact-sheet (fetched in-container 2026-09-02; read by the maintainer 2026-09-02): 'the bacterium can infect over 75 species of trees and shrubs, fire blight is also a significant disease of landscape plants including crabapple, ornamental pear, mountain ash, cotoneaster, hawthorn, firethorn, and quince'; 'The bacteria may be spread to blossoms, twigs, and branches by splashing rain, insects, and pruning tools'; 'Make the cut at least 8-12 inches below the edge of the infected area or canker.'

UMN Extension, 'Fire blight', extension.umn.edu/plant-diseases/fire-blight (fetched in-container 2026-09-02; read by the maintainer 2026-09-02): 'Heavy pruning and excess nitrogen fertilization stimulate excessive succulent growth of leaves and shoots. New growth and fast growth are very susceptible to fire blight infection'; 'carefully remove infected shoots during the growing season by cutting at least 12 inches below the infection point'; resistant apples Haralson, Liberty, Red Baron, SnowSweet.

Univ. of Illinois Extension, 'Fruitfulness and Pollination' (Fruit Trees for Home Gardens), extension.illinois.edu/fruit-trees/fruitfulness-and-pollination (read 2026-08-22): 'Self-fruitful trees may be planted alone or in solid blocks of one variety. Most peach, nectarine, and sour cherry varieties are self-fruitful'; 'A self-unfruitful tree will not set a normal crop of fruits when pollinated by its own pollen or by pollen of another tree of the same variety'; 'Self-unfruitful trees require pollination by pollen from a tree of a different variety'; 'A tree of a self un- fruitful variety should have a pollinator tree planted within 300 feet'; 'European-type plums will not cross pollinate most Japanese type plums'; 'Honey bees are the most important means of transferring pollen between blossoms.'

Iowa State Univ. Extension, 'Pollination Requirements for Tree and Small Fruits', yardandgarden.extension.iastate.edu/how-to/pollination-requirements-tree-and-small-fruits (read 2026-08-22): 'Fruit trees that require two different varieties for pollination should be planted within 50 to 100 feet of one another to ensure a good fruit set'; 'Apples are considered self-unfruitful. Most apple varieties will set a small crop with their own pollen. For maximum production, however, plant at least two different varieties with overlapping bloom periods to ensure cross-pollination and fruit set'; 'Most flowering crabapples will pollinate nearby apple trees if they bloom at the same time'; 'Most European pears are self-unfruitful. Plant at least two different cultivars for maximum fruit production'; 'European plums are partially to entirely self-fruitful'; 'European plums will not pollinate hybrid plums and vice versa'; 'Tart (also called sour or pie) cherries are self-fruitful'; 'Most peach cultivars are self-fruitful.'

Penn State Extension, 'Pollination Requirements for Various Fruits and Nuts', extension.psu.edu/pollination-requirements-for-various-fruits-and-nuts (read 2026-08-22): 'Apple: Cross-pollination is always needed to produce adequate fruit crop'; 'Pear: A few varieties are self-fruitful, but a pollinizer will improve the crop'; 'Plum: A wide diversity occurs in the plums. About half of the varieties are self-fruitful and half are not. To be on the safe side, pollinizers should be provided'; 'Red tart: The commercial varieties are self-fruitful'; 'Peach: All commercial varieties, except J. H. Hale, are self-fruitful.'