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

Publicado por lanechaffin lanechaffin, 17 de enero de 2019



This is a really helpful guide! Can you do one on oak tree species in Texas? I'm having a hard time with identifying ones I find in Tarrant County. The leaves never seem to match any of the suggested photos in the iNat app.

Publicado por joshuamanning hace más de 1 año (Marca)

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