Tree Species Identification and Care Reference

Why this reference exists

Pruning timing, removal difficulty, pest susceptibility, + customer expectations vary dramatically by tree species. A crew that calls a tree by name closes more sales + makes better technical calls. This guide covers the 30 most common U.S. residential trees in five regions, key pruning windows, common defects, + species-specific hazards.

Northeast + Midwest (cold winters)

Oak (Quercus spp.) - red, white, pin, bur, swamp white. Heavy hardwood; tough cuts. Susceptible to OAK WILT (Bretziella fagacearum). Prune November-February ONLY in any region with oak wilt confirmed. Slow growth, high value. Watch for two-leadered structure on young trees (split risk).

Maple (Acer) - sugar, red, silver, Norway. Sugar + red are valuable; silver is "weed maple" with high failure rate (V-crotch + brittle wood). Norway maple is invasive in many states. Prune late winter or summer (heavy spring sap flow). Watch for tar spot (cosmetic) + verticillium wilt (lethal).

Ash (Fraxinus) - green, white, black. EMERALD ASH BORER has killed billions. Most ash trees in the U.S. are dead or doomed unless on systemic insecticide. Removal upsell is huge; verify treatment history before quoting.

Birch (Betula) - paper, river. Pruning timing: late summer or autumn (heavy spring sap loss). Bronze birch borer kills paper birch in many regions; river birch is more resistant.

Elm (Ulmus) - American, slippery. Dutch elm disease still active. Prune October-March only. Many surviving Americans are 80-100 years old + valuable; care matters.

Pine (Pinus) - white, red, Scotch. Late winter pruning. White pine weevil + pine bark beetle are common pests.

Spruce (Picea) - Norway, Colorado blue, white. Late winter pruning. Cytospora canker common on blue spruce in eastern U.S.; many over-30-year specimens are declining.

Hemlock (Tsuga) - eastern. HEMLOCK WOOLLY ADELGID has decimated populations. Most hemlocks in northeastern states need systemic treatment or removal.

Southeast (warm + humid)

Southern Live Oak (Quercus virginiana): Florida + Gulf coast iconic. Massive horizontal limbs. Cabling + bracing is common upsell () to prevent limb failure on heritage trees.

Bald Cypress (Taxodium): swampy lots. Knees (root protrusions) are normal + should not be cut. Tolerates wet feet better than any other major species.

Loblolly + Slash Pine: timber species often left in residential plots. Tall, fast-growing, high failure rate in wind. Prune in any season; remove during winter to minimize bark beetle attraction.

Magnolia (Magnolia grandiflora): southern landmark. Prune AFTER bloom (late spring). Slow growth, valuable.

Pecan (Carya illinoinensis): nut producer; customers protective. Late winter pruning. Pecan scab common in humid summers.

Crape Myrtle (Lagerstroemia): ubiquitous southern landscape. "Crape murder" (topping) is malpractice + creates ugly knuckles. Selective thinning only.

Southwest + Desert

Mesquite (Prosopis): spreading, multi-trunk, thorny. Pruning timing flexible. Watch for sooty canker.

Palo Verde (Parkinsonia): green-bark desert tree. Susceptible to monsoon-wind failure due to shallow roots. Cabling is common.

Olive (Olea europaea): ornamental. Fruitless varieties common. Prune December-February. Verticillium wilt risk in heavy soils.

Citrus (Citrus spp.): orange, lemon, lime, grapefruit. Prune after harvest. HLB (citrus greening) is destroying commercial groves in Florida + Texas; expect to see infected residential trees too.

Date Palm + Mexican Fan Palm (Phoenix, Washingtonia): palm pruning is its own discipline ("skinning"). Annual frond removal. Don't over-prune ("hurricane cut") - strips green that the palm needs.

Pacific Coast

Coast Redwood (Sequoia sempervirens): largest U.S. residential tree species. Massive removal jobs . Drought stress visible at canopy top first; verify root zone moisture.

Douglas Fir (Pseudotsuga menziesii): dominant PNW conifer. Mistletoe + bark beetle issues common. Removal in residential settings often requires crane.

Western Red Cedar (Thuja plicata): PNW iconic. Decline syndrome widespread post-2015 drought.

Pacific Madrone (Arbutus menziesii): distinctive peeling red bark. Sudden Oak Death-resistant but other pathogens common.

Mountain West

Aspen (Populus tremuloides): clonal colonies, fast-growing, short-lived. Many residential aspens are 30-60 years old + at end of life. Cytospora canker common.

Lodgepole + Ponderosa Pine: bark beetle epidemic ongoing. Check for pitch tubes (popcorn-shaped sap globs) - sign of attack.

Blue Spruce (Picea pungens): stress + needlecast common in lower-elevation plantings.

Cottonwood (Populus deltoides): large, fast-growing, brittle, hollow-prone. Many large cottonwoods near houses are hazard candidates.

Universal hazard trees (identify on every site)

These species fail unpredictably + warrant a defect inspection on every visit:

• Bradford Pear (Pyrus calleryana): tight crotch, splits in storms. Quote replacement.
• Silver Maple (Acer saccharinum): brittle wood, V-crotch, hollow.
• Siberian Elm (Ulmus pumila): invasive in central U.S., weak wood.
• Willow (Salix spp.): shallow roots, brittle wood, septic-system-eating roots.
• Ailanthus / Tree-of-Heaven (Ailanthus altissima): invasive, fast, brittle. Resprouts from any root fragment.
• Norway Maple (Acer platanoides): invasive in northeast; girdling root mortality common.

Species-driven pricing modifiers

Some species cost more (or less) per inch:

Native vs invasive

Many trade associations + customers favor preserving native species + recommending removal of invasive species. Knowing the difference earns customer trust + repeats. Locally-published "native plant list" + "noxious weed list" from state DNR or extension service is the source-of-truth.

References

• USDA Forest Service Silvics Manual (online, free)
• ISA Tree Identification Guide
• State Extension Service tree-pest databases
• Native Plant Society + state DNR noxious weed lists
• Manuall internal: Tree Pruning Service SOP, Tree Removal Service SOP