Ulmus 'Androssowii'

The hybrid cultivar  Ulmus 'Androssowii' R. Kam. (or 'Androsowii' ), an elm of Uzbekistan and Tajikistan sometimes referred to in old travel books as 'Turkestan Elm' or as 'karagach' [:black tree, = elm], its local name, is probably an artificial hybrid. According to Lozina-Lozinskaia the tree is unknown in the wild in Uzbekistan, and apparently arose from a crossing of U. densa var. bubyriana Litv. (now Ulmus minor 'Umbraculifera'), which it resembles (see the disputed species Ulmus densa), and the Siberian Elm Ulmus pumila. It is sometimes listed as Ulmus × androssowii.

Not to be confused with the Ulmus 'Turkestanica' distributed by the Späth nursery of Berlin.

For U. 'Karagatch', see 'Hybrid cultivars' below.

For so-called Ulmus androssowii var. subhirsuta C. K. Schneid. and Ulmus androssowii var. virgata (Planch.) Grudz. , see Ulmus chumlia.

Description
The tree grows to a height of 20 m and is distinguished by its very dense spherical crown and pubescent leaves. Rehder noted (1939) that though similar in habit to 'Umbraculifera', 'Androssowi' could be "easily distinguished" by the grayish-brown bark of its twigs with conspicuous corky wings on older branches, by the pubescent winter-buds, by the mostly shallow- and single-toothed leaves, pubescent beneath, and by the near-orbicular fruit 10-13 mm in diameter, with the seed slightly above the middle. In 'Umbraculifera', by contrast, the twigs are red-brown and never corky, the leaves are more clearly and sharply double-toothed, only slightly pubescent beneath when young and soon smooth, and the obovate fruit is wedge-shaped at base and about 1.5 cm long, with the seed close to the notch. The compact branch structure of 'Androssowii' helps the tree conserve moisture.

Pests and diseases
Not known. In 1987, according to a Forestry Commission study of the Dushanbe area, Tajikistan, elms including 'Androssowii' "were plentiful in the city, pastures and roadside plantations, but no symptoms of Dutch elm disease, foliar or internal, were found. Breeding galleries of a Scolytus species close to Scolytus multistriatus were present in stressed or dying trees but no Ophiostoma ulmi was obtained from the galleries." The report concluded that, to date, the region may have escaped Dutch elm disease through geographical isolation.

Cultivation
The hybrid has been widely planted in southern and western areas of the former Soviet Union, notably along the streets of Samarkand. In western Europe it was distributed by Hesse's Nurseries, Weener, Germany, in the 1930s. A specimen was present at Kew Gardens in the 1930s. Cold-hardy, it prefers a rich soil and moderate humidity.

Hybrid cultivars
Ulmus 'Karagatch' is a hybrid cultivar from Turkestan, selected in the early 20th century and said to be either a backcrossing of U. pumila and U. 'Androssowii' or simply a cultivar of 'Androssowi'.

Synonymy

 * Ulmus Androssowi: Litv. in Schedae ad Herbarium Florae Rossicae 8: 23, no. 2445, t.2, 1922.
 * Ulmus pumila f. androssowii (Litv.) Rehd.

Accessions

 * North America
 * Morton Arboretum, Illinois, US. Acc. no. 353-72 (received as U. pumila f. androssowii (Litv.) Rehder ).
 * Europe
 * Grange Farm Arboretum, Sutton St James, Spalding, Lincolnshire, UK. Grafted cuttings acquired 2013. Acc. nos. 1095, 1096.
 * Hortus Botanicus Nationalis, Salaspils, Latvia. Acc. nos. 18165, 18166 (as U. pumila f. androssowii, both from Moscow).
 * Sir Harold Hillier Gardens, Romsey, UK. Acc. nos. 2016.0355, 2016.0356.

Nurseries

 * Europe
 * Pan-global Plants, Frampton on Severn, Gloucestershire, UK.