Archivos de diario de enero 2019

17 de enero de 2019

Identifying Redbuds in Texas

The botanical name for the Eastern, or American redbud is Cercis canadensis, and it is a member of the pea family, Fabaceae. Some taxonomists consider both the Texas redbud (Cercis canadensis var. texensis) and the Mexican redbud (Cercis canadensis var. mexicana) natural localized variations of the Eastern redbud.
In East Texas, in well-drained acidic soil, with regular moisture, the Eastern redbud (Cercis canadensis canadensis) in its typical form is found. It can be identified by its medium sized, dull green leaves, which, like all redbuds, emerge after the blossoms have fallen.

In Central Texas and southern Oklahoma, Texas redbud (Cercis canadensis texensis, formerly C. reniformis) is identified by its medium sized, glossy-green leaves and wavy margins, and its ability to tolerate drier, more alkaline soils. more suited to the harsher conditions of Dallas-Fort Worth, Austin and San Antonio landscapes.

The Mexican redbud (Cercis canadensis mexicana) is smaller in stature, ususally multi-trunked, and found in west Texas and northern Mexico. It is extremely drought tolerant, with smaller leaves and ruffled, wavier margins than the var texensis. The leaf pedicels and young branchlets of Mexican Redbud are densely woolly-tomentose and leaves slightly so. No doubt intermediate forms exist in various locations. Some botanist consider Mexican Redbud to be merely a hairy form of Texas Redbud instead of a distinct variety of Eastern Redbud. However, since forms resembling Mexican Redbud have been found in Dallas and Hood Counties it may be more likely to have derived from Eastern Redbud. Source: Robert A. Vines, Trees of Central Texas

All of these native redbuds have similar flowers in early spring. Typical redbud flowers are, of course, not red. They are normally in the purple-pink range, but also can be rosy pink or white.

Cercis canadensis range map

Ingresado el 17 de enero de 2019 por lanechaffin lanechaffin | 0 comentarios | Deja un comentario

Identifying Ash trees in Texas

White ash (Fraxinus americana) is native to the eastern part of the state. White Ash typically grows 50-80' tall (up to 125') and 40-50' wide. The lateral leaflets with stalks are strongly whitened beneath. Leaflets are often entire or with very shallow teeth. The bud scars are U-shaped. (Important: A leaf scar is the major botanical feature when keying a green or white ash. The white ash will have a U-shaped leaf scar with the bud inside the dip; the green ash will have a D-shaped leaf scar with the bud sitting atop the scar.) White ash 5-9 elongate leaflets, usually 7. The leaves are 8 to 12 inches in length, with individual leaflets 2 to 6 inches in length. White ash is typically a forest tree prefering moist, rich, deep soil and will grow well in a wide range of pH levels. Dark green leaves become yellow and/or deep purple and maroon in fall.

Some botanists believe that Texas ash (sometimes called Mountain Ash) is a smaller drought hardy variety of white ash (Fraxinus americana var. texensis), usually growing from 30-50' tall and 25-35' wide, from which it can be hard to distinguish. Texas ash (Fraxinus texensis) typically has 5-7 leaflets which are more rounded. Olive green to deep green leaves turn brilliant shades of orange, gold, purple or red in autumn. Texas ash is endemic to limestone areas of southern Oklahoma down through North Central Texas and across the Edwards Plateau.

Green Ash (Fraxinus pennsylvanica) typically grows 50-70' tall with an irregular crown up to 45'. sometimes called River Ash often found in riparian zones along rivers and creeks, floodplain forests and even inundated swamps, but it is adaptable to and often found in other growing environments as well. Green ash typically has 7 leaflets and is so named because the color of its leaves is green on both the upper leaflet surfaces and the lower leaflet surfaces. Lateral leaflets gradually narrowed at base into a narrow wing that runs down the upper part of the leaflet stalk. It is extremely variable in twig and leaf pubescence. Leaflets sometimes toothed. Its winter buds are brown and the bud scars flat-topped, half circles. Leaves are medium to dark green and become yellow in fall.

Berlandier or Mexican Ash (Fraxinus berlandier) is found in moist canyons and stream banks in Central Texas to Trans-Pecos Texas; southward into Mexico where it is called Fresno or Plumero. A smaller round-topped tree rarely over 30' tall. Widely planted as an ornamental in west and southwest Texas and Mexico. The leaves are dark green and thickish, 3-5 leaflets, lancelot or obovate, entire or remotely serrate, glabrous above, glabrous below or a few axillary hairs beneath.

Gregg Ash (Fraxinus greggii) Trans-Pecos found on rocky hillsides and arroyo banks. usually shrubby, to 25'. Leaflets usually 3, sometimes 5-7, thick, olive green above paler beneath, winged.

Fragrant Ash (Fraxinus cuspidata) is found in well drained soil in high altitudes in trans-pecos and in Mexico in rocky canyons. Shrubby, small tree to 25', sometimes forming thickets. Leaflets are 5-7, remotely serrate, lancelot or narrowly ovate, dark green, glabrous above paler below. This ash is unique in having floral fragrance and petals.

The Arizona ash tree (Fraxinus velutina) is commonly called the velvet ash and can reach 50' in height, with a 45-60' open crown in ideal conditions. It is an introduced species often sold at nurseries. Native range is in the high mountains and canyons of the Trans-Pecos and along streams, rivers, and dry streambeds. Marketed as being fast growing and drought resistant, but often problem prone and not recommended in most locations. However, the tree will thrive in less than ideal situations such as urban pollution and poor draining soil. Leaflets 5-7, occasionally 3. The upside and underside of the leaf are often tomentose. The leaf margin is serrated. Fraxinus velutina is closely related to Fraxinus pennsylvanica (Green Ash). Foliage turns yellow in autumn.

Fraxinus americana range

Fraxinus texensis range

Fraxinus pennsylvanica range

Fraxinus berlandier range

Fraxinus cuspidata range

Fraxinus velutina range

Ingresado el 17 de enero de 2019 por lanechaffin lanechaffin | 1 comentario | Deja un comentario

04 de enero de 2019

Id these sometimes difficult trees

*Ailanthus altissima (Tree of Heaven, Chinese Sumac)- Leaves alternate, aromatic, usually odd pinnate, 9-41 leaflets, entire leaf margin except near the base where 1-2 pairs of blunt dentate teeth usually occur, fall color yellow. flowers in spring, fruit samara. polygamo-dioecious. Introduced/non-native/escapes cultivation/invasive.

*Sapindus saponaria L. var. drummondii (Western Soapberry, Jaboncillo)- Leaves alternate, not aromatic, usually odd pinnate, rachis may be winged. 9-18 leaflets (terminal often absent), entire leaf margin, veins of leaflets off center fall color yellow. flowers in spring. fruit translucent amber drupe. dioecios. Texas native. often suckers and forms groves.

*Pistacia chinensis (Chinese Pistache) - Leaves alternate, slightly aromatic, usually even pinnate, occasionally will have terminal leaflet, esp on sapling trees. 10-16 leaflets, entire leaf margin, fall color orange/red. flowers in spring before leaves, fruit is small red drupe turns blue when ripe. dioecious. Introduced/non-native/escapes cultivation/invasive

*Rhus lanceolata (Prairie Flameleaf Sumac)- Leaves alternate, aromatic, odd pinnate, rachis may be winged. 9-21 leaflets, typically 13-17, entire leaf margin, or with small teeth, fall color red. flowers in late spring early summer, fruit red-brown drupe in tight cluster. diocecios. Texas native.

*Juglans nigra (Eastern Black Walnut)- Leaves alternate, aromatic, odd pinnate 13-23 leaflets, finely serrate leaf margin, fall color yellow. flowers in spring catkins, fruit is round nut. monoecious. Texas native.

Ingresado el 04 de enero de 2019 por lanechaffin lanechaffin | 3 comentarios | Deja un comentario