This is a detailed list of tree species starting with the letter E.
1. Earpod Tree, Pacara
Scientific Name: Enterolobium contortisiliquum
Native: Tropical America
Type: Evergreen or Deciduous
This fast-growing tree reaches heights of about 30m in its native habitat.
The tree has a single, erect trunk and is low-branching with a spreading crown. The bark is gray and rough, while the twigs are reddish-brown and have fine stripes.
The leaf is about 5 to 14cm long with a 4-6cm long petiole.
The tree bears leaflets in 12 to 16m segments with a lustrous medium green upper surface and a pale green lower surface.
The flower is bisexual and produced in headlike clusters colored creamy-white.
The fruit is a distinct earlike or kidney-shaped legume that is dark, coiled, and matures throughout the year.
Scientific Name: Diospyros ebenum
Native: India and Sri Lanka
This tree grows to 30m tall extremely slowly and has a trunk up to 90 cm in diameter in its native habitat but is much smaller in introduced regions.
The tree is well known for its durable black wood that has been used in Ceylon architecture. The tree bears hairless leaves that are rounded at the tip.
The fruit resembles that of the Common Persimmon but is distinguished by the rounded leaves.
The high wood hardness and ease of polishing make it extremely useful in commercial applications.
The species is considered endangered, and international trade is prohibited in India and Sri Lanka.
Scientific Name: Pouteria campechiana
Native: Mexico and Central America
This evergreen tree is also known as Canistel.
It grows to 25m tall with a trunk 1m in diameter but is usually smaller in introduced regions.
The trunk may be singular or multiple in number, and the tree has a broad spreading crown.
The bark is grayish and scaly. The leaves are closely set, elliptical in shape, and have a round and bluntly pointed tip.
The upper surface is yellow-green with conspicuous veins that give a quilted appearance to the leaf.
The flowers are bisexual and produced in axillary clusters of 1 to 9. The fruit is a large pear-shaped berry that may be yellow-brown, or orange.
The fruit bears hard, shiny brown seeds and matures primarily in winter.
4. Elder, Yellow
Scientific Name: Tecoma stans
Native: Western U.S.
Type: Evergreen or Deciduous
This tree is usually a shrub, also known as the Yellow Trumpetbush, and typically attains heights of 5 to 8m tall with a singular erect trunk and a broad, dense, and rounded crown.
The bark is furrowed and light grey in color.
The leaf is opposite, compound, around 10-25cm long and 7-13cm broad.
The tree bears leaflets in numbers of 5 to 13. The upper surface is dark green with conspicuous veins, while the lower surface is paler.
The flower is bright yellow, bell-shaped, and matures year-round. The fruit is a slender capsule around 20cm long and 5mm broad that matures year-round.
5. Elderberry, American
Scientific Name: Sambucus nigra
The American Elderberry, also known as the black elderberry, is a small shrubby tree that grows to 6m tall and has a diameter of about 20 cms.
It is often found in colonies and has underground runs. The tree has an ascending crown that is spreading.
The bark is grayish-brown and smooth, and the twig is brown, stout, and greenish. The leaf is opposite and has a blade about 15 to 25 cms long.
The upper surface of the leaf is dark green and has short hairs along the veins. The lower surface is pale green.
The flower is a small white structure with five petals borne in large, conspicuous inflorescences in the spring. The fruit is a shiny, juicy black berry-like drupe that matures in the summer. 
6. Elm, American
Scientific Name: Ulmus americana
This deciduous tree is 21 to 35m tall with a single straight trunk 50 to 120cm in diameter and a smooth, gray-brown bark that becomes ashy with age.
The leaves are simple, moderately stiff, elliptic and have a pointed tip. The upper surface is green, semi-shiny, and hairless while the lower surface is rouger to the touch.
The flowers are borne in clusters, and the fruit is a stalked samara.
Scientific Name: Paulownia tomentosa
This tree is also known as princess tree and grows from 18 to 20m tall with a 60cm diameter. It has a single, erect trunk with a round, spreading crown.
The bark is gray-brown and thin, the twig is stout, sticky when young, and has white lenticels.
The leaf is moderately thick with a heart-shaped base and pointed tip. The upper surface is dark green and hairy, while the lower surface is pale and more densely hairy.
The petiole is 5 to 21cm long and also hairy.
The flower is bisexual and fragrant. It may be lavender, pinkish purple, or purple on the outside. It is white or yellow inside with distinct purple to red spots.
The flowers are produced in large, showy clusters. The fruit is sticky, hard, and egg-shaped, becoming brown as it matures through the winter.
8. Enebro de Monte
Scientific Name: Juniperus ashei
Native: Texas hill country
This shrub or small tree is 15m tall with a diameter of 30cm to 50 cm and has a short single trunk.
The bark is pink when young, turning gray, followed by brown as the tree matures. The twig is stiff and 1mm.
The seed cone is 6 to 10mm in diameter, pink in color, subsequently maturing to dark blue, and having 1 to 2 seeds.
9. Enebro de Fruto Rojo
Scientific Name: Juniperus pinchotii
This shrub or small tree grows up to 6m tall and has multiple stems and several branches, forming an irregular crown.
The bark is smooth at first but becomes pale gray and flaky as the tree matures. The twig is stiff and 1mm thick.
The leaf is produced in whorls of three, having needle-like or scale-like shapes.
The seed one is 6 to 8mm in diameter, colored distinctly copper or copper-red. It is juicy, red, and typically has one seed.
10. Epicéa Commun
Scientific Name: Picea abies
This tree is about 40 to 50m tall and has a diameter of approximately 1 to 1.5m.
The crown is conical, and the bark is orange-brown and flaking, becoming gray-brown as the tree matures. The twig is an orangish-brown color.
The leaf is a rigid needle that is often blunt-tipped. The seed cone is 12 to 16cm long with a conical tip and a stiff upper margin.
This species is one of the most widely distributed conifers in the world and is a popular ornamental tree.
11. Eucalyptus, Grand
Scientific Name: Eucalyptus grandis
This evergreen tree grows to 55m tall, usually taller, with a 1.8m diameter in its native range. It has a single erect trunk with an oblong crown. The bark is shredding, revealing a white, grey, or green inner bark.
The leaf may be ovate with a rounded or heart-shaped base and a tapering tip that ends in a sharp point.
The upper surface is dark green, and the lower is pale gray.
The flowers borne have a vase-shaped bud and a pointed conical cap that falls off as the flower matures in the summer.
The fruit is a capsule of 8mm long and opens up to release around 25 heads.
12. Elbow Bush
Scientific Name: Forestiera angustifolia
Native: Southern Texas to Mexico
This evergreen shrub or tree grows from 1 to 4m tall and has a densely hairy twig.
The leaves are simple, leathery, and have a dark green color with a minutely hairy surface with dark pits on the lower surface.
The flowers are borne in small clusters with dark purple anthers from January to April. The fruit is an ovoid drupe that is dark blue, purple, or black.
This deciduous shrub or small tree is about 10m tall and has sharp, stiff prickles on its stem, branches, and leaf axes.
The leaves are a compound of numerous leaflets. The flowers are small, white, and 5-petaled, borne in clusters. The fruit is a round black or purple drupe.
13. Elephant Tree
Scientific Name: Bursera microphylla
Native: southern California
This deciduous shrub or small tree grows 2 to 5m tall with a diameter of around 50cms.
The bark is reddish and turns white as it matures.
The twig is flexible with short branches. The leaves are alternate, compound, narrow, and dark green with an odor. The flowers are white or cream and bloom in June through July.
The fruit is elliptical and may be a dull red or purple drupe.
14. Eve’s Needle
Scientific Name: Yucca faxoniana
Native: Western Texas to Northern Mexico
This plant grows to a large 7m tall with a single rosette of dense leaves.
The trunk is about 60cm in diameter, and the leaf is stiff, and tapering, resembling a dagger in a pale blue-green color.
The flower is bell-shaped, pendent, about 5cm long, and borne in dense clusters borne in March through May.
The fruit is a succulent and fleshy berry, green to tan in color, and becomes dry and spongy when mature.
This plant is a popularly grown ornamental in the southwest USA.
If you believe I missed any names, your suggestions for more species and genera are most welcome.
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