Willow; Sand-Bar Willow

Willow; Sand-Bar Willow Silax interior Rowley;.  Untypical of willows, this Silax is a low growing, tough, scraggly bush with narrow, leathery, toothed leaves alternating along straight, brittle stems.  This willow reproduces from roots as well as seeds, forming expanding clumps.  Although it prefers alluvial sand and gravel along stream beds and road-side ditches, it is often found on bare limestone, even where there is no shallow water table.  New shoots can bud from nodes along old stems or trunks, giving it a brushy, bristly appearance.  Plants are either male or female.  Both produce catkins, but female catkins are much larger (2-3”) and are the only ones to convert, in the fall, to masses of white, fibrous achenes that carry seeds on the wind.  (96) 4/22/17- ; 18 no obs (achenes 10/20/18); 19 no obs; 20 no obs;

Sandbar Willow habit; a scraggly, arching bush found along road ditches, alluvial gravel beds or bare limestone, with long, narrow, toothed foliage and tiny catkins, which in female plants, convert to tufted, fibrous achenes.

Note; new shoots grow from old trunks, making them look scraggly and rough

Note; the dark grey bark is rough and thin, but lacks corky ridges

Note; long, strap like leaves with coarsely toothed margins are born alternately along new stems

Note; fall flush of achenes turn female plants white with what look like flowers

Note; panicles of tuft like achenes

 

Eastern Black Walnut

Walnut; Eastern Black Walnut Juglans nigra L;. A large, low branching, slow growing, deciduous forest tree, with thick, deeply furrowed, black to dark grey, corky bark, Walnuts are more common in Eastern Forests where there is abundant rainfall.  DFW is on the margins of Walnut habitat, a few specimens growing along the north facing slopes of water cut canyons along the MK Trace.  The compound pinnate leaves, over a foot long, each have up to 17 slightly toothed, lance shaped leaflets, born in opposite pairs, with a final solo leaflet.  Catkins are produced in April off the ends of last year’s stems, at the same time new leaves are budding.  Catkins, which look like strings of warty knobs, convert into round, green nuts up to 2” in diameter, which turn black after they fall.  Inside this fibrous husk (3/16” thick), lies a very hard, round, nut 1″ to 1½”  in diameter, with deep convolutions, that can only be cracked open with a hammer (rock or iron).  The flesh of the nut is lobed like an English Walnut, but is somewhat spicy, once commonly used to flavor ice-cream.  Tiny maggots eat much of the pulp away from the seed as it rots on the forest floor.  Black Walnut wood is dense, dark brown with nearly black grain, but often bored through by wood beetles.  Texas black walnut (Juglans microcarpa), found west of DFW, has much smaller seeds, as the name micro– implies. (123-124) 4/18/15; 4/22/16; 3/28/17 – 4/10/17; 4/17/18; 4/20/19; 4/13/20 – 4/20/20;

Eastern Black Walnut habit; a large, readily branching canopy tree with a loose crown, long compound pinnate leaves, and dense, dark brown heart-wood with black veining, bearing very hard nuts encased in fibrous casques

Note; deeply furrowed, thick, black to dark grey, corky bark

Note; long compound pinnate leaves with odd numbers of leaflets, opposite pairs and a final lone tip leaflet, each lance shaped with a slightly serrated margin

Note; pendulant catkins that look like strings of warty knobs bud from the ends of last year’s twigs as new leaves are growing out

Note; large, round, green fruit which turn black after they fall, composed of a thick, fibrous rind surrounding a very hard, thick nut with spicy, white meat.

Note; the hard, convoluted nut embedded within an inedible, fibrous casque, green when it falls, turning black with age

Sumac, Skunk-Bush Sumac

Skunk-bush; Skunk-Bush Sumac Rhus aromatica var. flabelliformis Shinners;.  This tough, low-growing, evergreen shrub has three lobed leaves with rounded lobes (not pointed like Poison Ivy) born in an alternating pattern on thin, grey stems.  The leaves have a strong smell when crushed or cut, earning it the nick-name “Skunk-Bush”, although they do not smell remotely like skunk.  The scientific name ‘aromatica’, is more generous, though the smell is more offensive than aromatic.  Common in wooded areas of thin soil covering chalk limestone, skunk bush is nearly inconspicuous until winter, for the leaves are evergreen and the hairy fruit a dull red.  The tiny but fragrant, inconspicuous, greenish-white flowers open in mid March.  The fruit are little more than a thin, hairy skin covering a large, hard seed.  (630) 3/27 – 4/6/15; 17 no obs; 18 no obs (drupe 5/25/18); 3/25/19 (drupe 5/18/19); 20 no obs;

Skunk Bush habit; a low growing evergreen shrub with grey stems, alternating, three lobed leaves, and compact bunches of hairy, dull red berries

Note; trifoliate leaves, each leaflet with three rounded lobes, are not sharply pointed like Poison Ivy, and have a strong, offensive odor when cut or crushed

Note; tiny, inconspicuous, greenish flowers are born in short spikes from leaf axils

Note; terminal clumps of fragrant flowers open as new leaves are growing in

Note; clumps of hairy, dull red fruit, little more than thin skin covering hard seeds

Privet; Chinese Privet

Privet; Chinese Privet Ligustrum sinense Lour;. This leggy, drooping, invasive, evergreen ornamental shrub was imported for its terminal spikes of fragrant white flowers and green foliage.  Privet sports multiple, small, trunk like stems which sprout from a central, shallow, bulbous root, sprouting new growth from the base and from branches in March, then developing terminal sprays of flowers which open in April or May.  Flowers convert to small, oblong, blue-black fruit that soon ripens, but does not fall until the next spring (March).  The mass of showy, fragrant flowers are white, with 4 elongated petals, arranged around a short tube, from which two filamentous stamen protrude, each tipped with a purple anther.  Pointed, elliptical leaves are born in opposite pairs along new stems, remaining for several years.  The long thin, brittle new shoots are easily snapped, but grow back quickly, gradually bending over if not supported, till they touch the ground. They will take root if they touch, so privet needs to be cut back twice a year to keep it in check.  Older trunks develop a knobby surface with sharp, spike like protuberances where opposite leaf ribs once grew. This privet has taken over large areas of moist bottom land, forming interlaced understory thickets that are nearly impenetrable without a machete or hardy nippers.  The roots are shallow and the stumps easily removed, but Privet can grow back from roots.  Privet does not colonize open grass land, as it does not tolerate full sun. (857) 4/25/15; 5/25/16; 4/18/17- ; 4/18/17; 5/20/18- ; 5/4/19; 5/15/20

Chinese Privet habit; an evergreen shrub with multiple, long, arching trunks radiating out from a central, shallow, bulbous root, stems taking root wherever they touch the ground, bearing attractive elliptical leaves and terminal sprays of fragrant white flowers

Note; evergreen, dark green leaves born in opposite pairs along stems.

Note; showy, terminal panicles of fragrant white flowers, each with four elliptical petals, and two white stamen tipped with purple anthers.

Note; each flower has four elongated, slightly curled, white petals arranged around a short, central tube from which two stamen, tipped with an anther, protrude

Note; flowers convert to black/dark blue, oval to round berries, eaten by many migrating birds

Poison Ivy

Poison Ivy; Poison Ivy Toxicodendron radicans L;.  A variable, noxious plant that grows as a clinging vine on tree trunks, or free-standing as a low, weak, or sprawling plant with reddish stems which sports coarsely toothed trifoliate leaves, and occasionally white berries.  Clusters of tiny (3/16”) green and yellow flowers, composed of 5 fleshy petals arranged around a yellowish disk of stamens and a white pistol, bud from old leaf scars, turning into smooth white berries, which some birds can eat without ill effects.  The glossy, compound leaves come in sets of three leaflets, each of which is deeply indented into three or five pointed lobes.  The leaves are generally small (2-3”) in upright plants, but much larger (4-6”) in the vine form.  Some vine forms have an extra set of leaves, arranged as a compound leaf of 5 leaflets. Vines attach to tree trunks with dense mats of roots, much like Virginia Creeper, but can be easily stripped off.  Rhizomes burrow through leaf litter, spreading underground.  The general rule, “Leaves of three, leave them be” was coined to warn people of the bad rash touching Poison Ivy leaves can induce.  Although there are other plants which bear leaves in sets of three (Ash, Hops, Skunk Berry), they are shaped differently.  Poison Ivy prefers acid soils around Juniper trees, reaching larger sizes near water.  Goats can graze the leaves with no ill effects.  Poison Ivy rash generally lasts two weeks, but lathering the rash with Burt’s Bees poison ivy soap can cut down on the itch and shorten the duration to days.  If exposed to leaves, wash with soap and cold water, as hot water may drive the poison into pores.  Do not attempt homeopathic remedies that involve drinking tea made from the leaves, for this has led to horrible reactions.  A few lucky individuals seem not to react to poison ivy.  Poison ivy cannot tolerate full sun, and is easy to eradicate by pulling runners out of the ground (guarding the skin with rubber gloves).  Do not burn dried plants, as the smoke can carry the toxic resin into the lungs. Leaves turn a dark red in the Fall.  (638-641) 4/13/15 – 5/15/15; 4/5/16; 3/10/17 – 4/10/17; 18 no obs; 4/1/19; 4/9/20;

Poison Ivy habit; a variable plant that may be a free standing, weak reddish stem, or a vine that climbs trees with short clinging roots, like Virginia creeper, or an Ivy, with trifoliate leaves and small greenish-yellow flowers that convert to white berries.

Note; glossy green leaves come in sets of three pointed, egg-shaped leaflets with coarsely toothed margins.  Some leaves have 5 leaflets.

Note; small spikes of greenish, fleshy flowers with five petals arranged around a ring of yellowish stamen, with a central, white pistol, are born from old leaf axils.

Note; flowers convert to greenish berries, which turn white when mature.

Note: leaves turn bright red in the fall

Pecan

Pecan; Pecan Carya illinoensis Koch. Better known for the commercially grown Paper-Shell Pecan, which have larger nuts with thin shells, native Pecan (known as Nueces in Mexico) tend to be a smaller tree, which have smaller nuts with hard shells.  Pecans are a tall, deciduous tree with lanky, brittle branches, lined with flaking rather than corky bark.  The compound pinnate leaves have an odd number of elliptical leaflets with smooth margins, the leaflets arranged in opposite pairs along a central rib, with a single leaflet at the tip.  The wood is soft and brown, and has a strong odor.  Catkins appear in spring, budding from the leaf axils of new growth.  The fruit begin as oblong, green ovals with four ridges, nuts ripen in October-November as the fibrous casques ripen, turn black and split along the seams, allowing the nut to fall out, or be shaken out.  Nuts with the husks still attached are usually spoiled.  Though no wild Pecans grow in the ILC, they are plentiful in other forested areas, constituting an important winter food source for rodents and wild boar.  Many domesticated trees, grafted from Paper-Shell cultivars, have been planted on the ILC.  (127-128 Vines) 5/1/20

Pecan habit; a very tall, leggy tree with scaly rather than corky bark, bearing alternating, compound pinnate leaves and reproducing through catkins which convert to clusters of edible nuts

Note; catkins are produced from new growth after the leaves have budded out

Note; compound pinnate leaves arranged in an alternating pattern around stems have an odd number of lanceolate leaflets with finely serrated margins, arranged as opposite pairs with one terminal leaflet

Note; green, oblong fruit, in clusters of 3-5, are composed of a fibrous casque, split by four seams, surrounding a thin shelled nut.

Note; husks turn black and split along seams, allowing the smooth, brown nuts to fall out

Oak; Post Oak

Oak; Post Oak Quercus stellata Wangh,. The white to light grey bark of this slow growing, deciduous, irregular shaped tree comes in loose chips rather than deep fissures.  The bulbous base is often surrounded by shoots, forming an island of wispy suckers, a few of which can become secondary trunks, or the main trunk, should the trunk die.  The light green, irregular, three lobed leaves are rounded, rather than sharply pointed, like Red Oak.  Leaves are frequently infested with reddish or greenish fruit-like galls.  A grub lives in a small hard knot in this gall, suspended by a fibrous network inside.  Catkins (small spikes of tiny flowers) emerge from the ends of last year’s stems after new leaves have sprouted.  The small acorns are nearly round, with a sharp tip. Cut branches or trunks reveal the typical radiating pattern of oaks, but do not form the dark heart-wood of red oak.  Useless for lumber, the wood was most often split into fence posts and rails, lending the tree its scientific, and local name (rails/posts).  Locally it is most common along the chalky escarpment and slopes, often in a tangled, shrubby form, but it can grow to very large size over time.  Forests of this tree are common between Wichita Falls and Vernon Tx along 287. The stately, knurled Big Tree (on Big Tree Circuit), the largest tree on the ILC, is a Post Oak.  (154-155) 4/3/15; 3/25/16; 3/10/17-3/28/17; 3/25/18 – 4/10/18; 3/25/19 – 4/1/19; 3/25/20;

Post Oak habit; a slow growing, often knurled looking, deciduous oak with crooked branches, an irregular crown and scaly (rather than furrowed) bark that produces very small acorns

Note; light grey bark that is scaly, rather than furrowed

Note; often with multiple trunks, or at least islands of green wispy suckers growing around a bulbous base.

Note; leaves, arranged in an alternating spiral, have three to five smooth lobes with rounded tips.

Note; catkins emerge from last year’s stems after new leaves have grown in

 

Note; leaf galls, often red, called “cherry galls” are composed of a thin, warty shell surrounding a hard core suspended by radiating white filaments

Note; small, nearly round acorns with a sharp drip tip.

Oak; Live Oak

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Oak; Live Oak Quercus virginiana Mill;. Dallas is beyond the northern edge of the natural range of live oaks, but the trees grow here if planted and watered for the first few years.  The deeply furrowed, rough, black bark of this readily branching evergreen contrasts with the glossy dark green of its small (<2”) evergreen leaves, which depending on the variety, range from slightly curled with sharp holly-like points, to smooth and elongated ovals.  The leaves last for two or more years, older leaves shedding in the spring just before new leaves grow in (mid-March).  Live Oaks reproduce from catkins, tiny spikes of miniscule flowers, a few of which convert to acorns that are much longer than most oaks, often turning bronze in color after they fall.  The slow growth, spreading growth pattern, drought resistance and evergreen qualities make this tough, dense-wooded tree a favorite for large yards or campuses.  Though the long, drooping, habit of new growth gives this oak a scraggly look when young, it usually grows wider than tall, achieving a manicured, rounded profile.  The tough, dense, springy wood, favored by ship-builders, allows the branches to extend far outward, making them safe for kids to climb in without fear they will breaking.  The leaves and bark, are so heavy with tannin that they do not make good mulch.  The acorns, longer than other types of oak, end in a terminal spike, and held in exceptionally small caps, are green when they fall, but soon turn a rich brown.  They sprout easily, if they escape acorn weevils, and form an enlarged, woody, tuber-like base just underground which preserves young tree through dry periods.  Light brown, woody galls caused by tiny wasps, form on twigs. (170-171) 4/10/15; 3/26/16-4/15/17; 3/22/18 – 4/10/18; 3/25/19 – 4/20/19; 3/25/20 – 4/17/20;

Live Oak habit; a slow growing, evergreen oak that branches readily, with dark grey to black, deeply furrowed (or cubed), corky bark, and very dense, springy, hard wood that produces elongated, rich brown colored acorns.

Note; nearly black, deeply furrowed, corky bark, often broken into cubes, rather than ridges, with a spreading habit

Note; long, tough, dark green leaves, sometimes with tooth-like projections along the margins, which shed just before catkins and new growth appear in the spring

Note; fuzzy catkins which emerge just as the tree is budding new, wispy growth with fresh leaves

Note; grey stem galls caused by a tiny wasp.  These are not the fruit of the tree

Note; acorns are long and thin, with a sharp tip, and a very small cap, green when they fall, but turning a rich brown after a few days.

Note; rich brown color, extra small cap, elongated form, and tiny hole where a wevil larva exited.

Oak; Bur Oak

Oak; Bur Oak Quercus macrocarpa Michx;. A large, deciduous, relatively fast growing (for an oak!), open crowned tree with huge 2” acorns and gigantic (6-12”), undulating leaves that are deeply cut, each lobe having rounded corners rather than pointed tips.  The dark grey, corky bark is deeply furrowed, and the brown heart-wood is surrounded by 4” of tan sap-wood.  Oaks produce catkins, tiny spikes of miniscule flowers that look fuzzy, from the tips of last year’s stems, just as new shoots are budding.  Bur Oak bears the largest acorns of all oaks earning it the scientific name macro-carpa ‘big-fruit’. The deep acorn cap, fringed with stiff, burr-like curled fibers, enfolds over half the acorn, from which the common name ‘burr oak’ is derived.  Locally, the natural range of Bur Oak is the bottom lands or flood basins, where there is deeper soil and more water, but it will grow in shallow soils if watered for years.  It is an impressive tree, but due to its irregular shape, size and loose crown, is not commonly grown in yards. (148-149) 4/10/15; 3/25/16-? ; 18 no obs; 3/25/19-4/1/19; 3/25/20

Burr Oak habit; a large, open crowned tree native to moist bottom lands with deeply furrowed bark, huge acorns and long, undulating, rounded leaves.

Note; thick, deeply furrowed, dark grey, corky bark covers thick sap wood.

Note; gigantic (6-12”), undulating leaves with deep sinuses dividing lobes with rounded tips

Note; catkins bud from tips of last year’s stems just as new shoots are sprouting (March-early April)

Note; huge acorns up to 2” long, mostly concealed by a rough, scaly cap with a fringe of stiff, burr like hairs.

Mulberry; Texas Mulberry

Mulberry; Texas Mulberry Morus microphylla Buckl;. A rather small specimen of mulberry, M microphylla is more of an evergreen, scraggly understory bush than a tree, but still has the classic features of mulberry trees; male and female flowers, soft, heart shaped to multi-lobed leaves with a finely toothed margin, smooth trunks with a thick fibrous inner bark, and fruits that are a tight cluster of juicy berries that turn red or black when ripe.  Pistols protrude from the berries of Texas Mulberry, giving the fruit a rough texture, but they are safe for humans.  Relished by birds, much of the rather small fruit drops to the ground where it is rapidly eaten by raccoons, opossum, and even coyotes.  Mulberry are mostly found in forests on north facing canyon walls where there is ample runoff, deeper soils, and protection from summer sun, but the shallow, spreading root system allows this Mulberry to live in the thin topsoil of the limestone plateau on top of the escarpment. (219-220) 4/7/15 (drupe 5/14/15); 3/27/16; 3/12/17-3/25/17; 18 no obs (drupe 5/25/18); 4/7/19 (drupe 5/25/19); 3/25/20 (drupe 5/6/20);

Texas Mulberry habit; a scraggly understory bush with smooth bark, alternating, multi-lobed, rough, toothed leaves with drip tips and small catkins that convert to small, juicy, red fruit.

 

Note; rough textured leaves with 4 deep sinuses that divide them into 5 lobes

Note; the distinct drip-tips, and the toothed margin of the alternating leaves

Note; small, fuzzy catkin flowers budding from the leaf axils of new growth convert to small, juicy fruit that turns red when ripe.

Note; the protruding pistols give the compound berries a prickly texture