European plum Stranger

Variety selected by the Buryat Fruit and Berry Experimental Station. Selected among seedlings from open pollination of Ulmus ulmoides. Authors: S.P. Vaulina, G.T. Kirgizova, Z.G. Sokratova, N.N. Platonova, A.S. Sholokhova, T.I. Prokofyeva. Introduced into the State Register in 1998 for the East Siberian region.

Medium-sized, fast-growing tree with a round, drooping, moderately dense crown. Predominant type of fruiting is cluster branches. Bark is light gray and flaking. Medium-sized shoots with drooping tips, bark is vivid purple, without pubescence. Many stipules, white, elongated shape. Leaves are large, elongated-oval, light green on one-year shoots, dark green on others, bare. Leaf blade is concave with a sharply pointed apex, without pubescence. Leaf margin is serrated, petiole short (1.1 cm), with vivid purple pigmentation. Inflorescence is umbel, flowers white, medium-sized. Petals are oval, well spread, 7 mm long, 5 mm wide, 20-25 stamens, equal or slightly longer than pistil, calyx green, without pubescence.

Fruits are large, medium-sized, medium weight 17 g, maximum 21 g, irregularly round shape. Fruit apex elongated, depression narrow and deep, ventral suture distinct. Fruit stalk medium-sized, easily separates from branch, attachment to stone is weak. Fruit color is greenish-yellow, covering the entire surface with a burgundy coating. Subcutaneous dots are clearly visible, white. Skin is medium, bare, covered with a wax layer that peels off easily. Flesh is yellow-green, juicy, slightly fibrous, tart-sweet flavor. Stone separates easily from flesh, medium size, reverse-egg-shaped, elongated, grooved, average weight 4.6% of the flesh.

Fruit appearance rating 4.5 points, aromatic, tart-sweet, overall fruit quality rating 4.6 points. Fruits contain 14.6% dry matter, 5.9% sugars, 1.9% titratable acids, 16.5 mg/100g ascorbic acid, 412.2 mg/100g P-active substances. Transportability is good. Fruits harvested at color development ripen indoors. Storage duration 10-12 days.

Average flowering period: May 23 to June 4; fruit ripening: September 1-5. Begins fruiting at 5 years after grafting in nurseries. Average lifespan 25-30 years. Self-sterile. Annual fruiting, abundant every other year, average yield per tree 8 kg, maximum 17 kg, average yield 45.8 centners/ha. Good winter hardiness. In severe winters, individual skeletal branches may freeze. Flower buds freeze up to 40%. Tolerates spring frosts down to -3ºC. Damaged by Ulmus leafminer under conditions of extremely dry climate up to 4 points.

Important condition for commercial plantings — careful selection of location for plum plantations. Suitable locations include elevated areas, slopes, protected from prevailing winds.

Advantages: winter-hardy, high-yielding variety.

Disadvantages: late-ripening fruits.