BOTANY WITH BASICS OF HYDROBOTANY (AQUATIC PLANTS OF UKRAINE) - B.Ye. Yakubenko - 2011

X. SEED PLANTS

Willow Family (Salicaceae)

Trees or shrubs, typically dioecious. Leaves alternate, simple, with stipules that sometimes drop early. Flowers unisexual, without perianth, located in the axils of bracts and gathered into simple inflorescences known as catkins. Staminate flowers have from two to 40 stamens, while pistillate flowers possess a single pistil formed by two fused carpels; the Ovary is superior, unilocular, containing numerous ovules. Flower formula: staminate - ♂A_2-40, pistillate - ♀G₍₂₎. Fruit is a two-valved capsule. Seeds are small, endosperm-less, with a tuft of hairs at the base. Willows bloom early, either before the leaves unfold or simultaneously with them. They are fast-growing, moisture-loving, short-lived plants that easily propagate vegetatively. Their practical uses are diverse: the wood serves as a local building material and fuel, and is utilized in paper production and various crafts; the bark is used for tanning leather and extracting salicin; young shoots of certain shrubby willows are woven into baskets, and so forth. Some species are cultivated as ornamentals, planted along roads, avenues, Water bodies, earth dams, ravines, and gullies, or used for sand stabilization.

The family comprises three genera and 550 species, distributed mainly in temperate zones. In Ukraine, this family is represented by two genera and 40 species.

Bilberry willow (Salix myrtilloides L.). A shrub 0.2-1 m tall; helophyte (sphagnophyte), entomophilous, anemophilous, anemochorous. Branches are slender, yellowish- or reddish-brown. Phyllotaxy is alternate. Leaves are 1-3 cm long, 0.6-0.9 cm wide; rounded-ovate or elliptic, entire or with scattered Teeth and a dense reticulate venation. Blooms in May. Fruit is a narrow, almost awl-shaped capsule. Seeds are pubescent.

Grows in bogs, predominantly mesotrophic, sedge-sphagnum, and occasionally sedge-hypnum wetlands; frequent in Polissia, rare in the Volyn Forest-Steppe. Under conservation status, listed in the Red Data Book of Ukraine.

Lapland willow (Salix lapponum L.). A shrub 0.5-1.5 m tall; helophyte, entomophilous, anemochorous. Leaves are lanceolate, obovate, with wrinkled apices, white-tomentose beneath, nearly entire, up to 25 cm long. Stipules absent. Generative buds are oblong-ovate, exceptionally thick, exceeding the SHOOT diameter. Catkins are 3-4 cm long. Stamens two, anthers violet-yellow, ovary white-tomentose, style and stigma long. Fruit is a sessile capsule. Blooms in April - May.

Occurs frequently in the peaty bogs of Polissia, rarely in the Volyn Forest-Steppe and Roztochia; a single locality is reported in the Carpathians, though its current persistence remains uncertain.

Dark-leaved willow, blackish willow (Salix myrsinifolia Salisb., S. nigricans Smith.). A shrub up to 3 m tall; helophyte, entomophilous, anemochorous.

Leaves are highly variable in shape: obovate, rounded-ovate, oval, oblong-lanceolate. The pubescence color at the Base of the shoot and on the upper leaves is glaucous, on intermediately positioned leaves partially glaucous, and green on the lower ones. Leaves turn black during herbarization. Stipules are usually well-developed. Stamens two, pubescent at the base. Ovary long-stalked, glabrous, style long. Blooms in April - May. Fruit is a capsule, glabrous or pubescent, gradually tapering into the style.

Inhabits waterlogged meadows and shrubby bogs, primarily on peaty soils. Rarely found in the northern districts of Polissia and Roztochia (reaching the outskirts of Lviv).

Starke's willow (Salix starkeana Willd.). A shrub 0.5-3 m tall; helophyte, entomophilous, anemophilous, anemochorous. Branches slender, brownish, branched. Phyllotaxy alternate. Leaves 2-6 cm long, 1.5 cm wide, broadly lanceolate, flat, unwrinkled, glabrous, glaucous beneath, serrate at the margin. Generative buds triangular-lanceolate with a flattened apex. Blooms in April - May. Fruit is a capsule.

Grows in river floodplains, eutrophic bogs, and shrub thickets. Sparsely distributed across Polissia, the Forest-Steppe, and the Steppe zones. Protected by law, included in the Red Data Book of Ukraine.

Swampy