African Sumac Tree: Desert Shade Pros, Cons and Pollen

An african sumac tree can look like the perfect answer for a hot desert yard: evergreen, drought tolerant, graceful and dense enough to cool a patio in July. It also drops fruit, sheds leaves year round, spreads surface roots and, on male trees, releases pollen that has led some Southwest cities to restrict new plantings. Whether it belongs in your yard depends on where you plant it, which sex you buy, and how close it sits to the pool.

Gardeners in Phoenix, Tucson, Las Vegas and Southern California have used this tree for decades because it handles heat and alkaline soil with little complaint. In the right spot, far from paving and water features, it delivers reliable shade for a long time. In the wrong spot, it lifts patios, litters pool filters and seeds itself into nearby beds.

What Is an African Sumac Tree?

The african sumac tree (sometimes called karee in its native southern Africa) is a small to medium evergreen that typically reaches 20 to 30 feet tall with a similar spread. Leaves are narrow and grouped in threes, giving the canopy a fine, willowy texture. Older trees develop a dark, rugged trunk, often with multiple stems, and a slightly weeping crown.

It is hardy to roughly the high teens Fahrenheit once established, which suits USDA zones 8 through 11. Hard freezes below that can damage foliage and young branches. Growth is moderate to fast with regular water, often 2 feet or more per year when young.

Drought Tolerance and Watering

Few shade trees match it in drought. Once established, usually after two to three years, it gets by on deep watering every two to four weeks in summer in low-desert climates and much less in winter. It tolerates reflected heat from walls and pavement, alkaline soil and poor, rocky ground.

Young trees are another story. For the first summer or two, water deeply once or twice a week, soaking the full root ball and the soil just outside it. A slow-release tree watering bag around the trunk makes this easy in the first season, because it delivers water slowly to the roots instead of letting it run off hard desert soil. After that, move drip emitters outward to the drip line as the canopy grows, adding emitters rather than just running the system longer.

• Too little water: sparse canopy, leaf drop, slow growth.
• Too much water: rapid weak growth, shallow roots and higher odds of the tree toppling in a monsoon storm.

Messy Fruit on Female Trees

African sumac is dioecious, meaning trees are either male or female. Female trees produce clusters of small, pea-sized fruits that ripen from green to tan or brown. They drop onto patios and decks, stain light pavers, and float into pools, where they clog skimmer baskets. Birds eat some of the fruit and spread seeds, so volunteer seedlings often appear in gravel beds and along walls.

Leaf litter is the other cleanup issue. Being evergreen does not mean the tree never drops leaves; it sheds a steady trickle of older leaves throughout the year, with heavier drop in spring. Near a pool, that adds up to more frequent skimming and filter cleaning.

Pollen Restrictions in Some Cities

Male trees release large amounts of fine, wind-carried pollen in late winter and early spring, and that pollen is a known allergy trigger. Several desert-area cities and counties have pollen-control ordinances that limit or prohibit planting certain high-pollen species, and African sumac has been on those lists in some places. Rules vary, change over time, and sometimes only apply to new plantings, so check your city or county code before you buy.

This creates a trade-off. Male trees mean no fruit but more pollen. Female trees mean less pollen exposure for the household but more fruit cleanup. Young nursery trees are often not labeled by sex, so ask the nursery whether the tree was grown from a known cutting. If allergies run in the family, a different species may simply be the better choice.

Root Behavior Near Pools and Patios

African sumac roots are generally not as aggressive toward pipes as willows, but the tree does form strong, shallow surface roots, especially when it has been watered lightly and often. Those roots can lift concrete decking, crack pavers, push on low walls and invade loose gravel beds. Around pools, the combination of roots, fruit and leaf litter makes it a poor neighbor.

1. Plant at least 15 to 20 feet from pools, patios, driveways and walls.
2. Water deeply and infrequently to push roots downward instead of along the surface.
3. Avoid planting directly over irrigation mains or pool plumbing.
4. Call 811 before digging so buried utilities are marked.

Planting Steps

1. Choose a full-sun site with room for a 25 to 30 foot canopy.
2. Dig a hole two to three times as wide as the root ball and no deeper than the ball.
3. Set the tree so the root flare sits at or slightly above grade.
4. Backfill with native soil; skip rich amendments, which encourage roots to stay in the hole.
5. Build a low berm to hold water, then soak thoroughly.
6. Add 2 to 3 inches of mulch or decomposed granite, keeping it away from the trunk.
7. Stake only if needed for wind, and remove stakes within a year.

Pruning for Strength and Clearance

Multi-trunk trees look attractive, but crowded stems with tight unions are prone to splitting in monsoon winds. Prune in late winter or early spring to select three to five well-spaced trunks, remove crossing branches and thin the crown so wind can pass through. Avoid lion-tailing (stripping all inner branches and leaving tufts at the ends), which makes limbs heavy at the tips and more likely to break.

Raise the canopy gradually to clear walkways and sightlines. Remove sprouts at the base and volunteer seedlings in nearby beds while they are small.

Seasonal Care Calendar

A simple yearly routine keeps an african sumac tree healthy and cuts down on cleanup surprises. Desert climates have two stress seasons, early summer heat and the monsoon wind season, so most of the work centers on getting the tree ready for both.

• Late winter: structural pruning, removal of dead wood and thinning before spring growth. Check drip emitters and move them outward if the canopy has expanded.
• Spring: expect heavier leaf drop as new foliage pushes out. Pull volunteer seedlings while the soil is still soft, and top up mulch to about 3 inches.
• Early summer: extend watering run times rather than increasing frequency. Watch for aphids on new growth.
• Monsoon season: inspect the canopy for crowded or crossing limbs before storms arrive. After big wind events, look for cracked branches and leaning trunks.
• Fall: taper irrigation as temperatures drop. Rake fruit from patios on female trees before it stains pavers.

Fertilizer is rarely needed. In very alkaline soil, a light application of a product made for desert trees in spring can help with pale foliage, but deep, infrequent watering does more for overall vigor than feeding.

Troubleshooting

• Tree uprooted or leaning after a storm: often caused by shallow, frequent watering and an overly dense crown. Deepen irrigation and thin the canopy.
• Yellowing leaves: may signal overwatering in heavy soil or nutrient issues in very alkaline ground.
• Sticky residue on cars or patios: usually aphids or scale; a strong spray of water or labeled horticultural oil helps.
• Seedlings everywhere: a female tree nearby. Pull them early and mulch bare soil.

Alternatives for Desert Shade

If pollen rules, pool cleanup or root concerns rule out African sumac, these trees are widely planted in the Southwest:

• Palo verde hybrids: filtered shade, yellow spring flowers, very low water.
• Desert willow: small, flowering, deciduous, light litter.
• Chinese pistache: deciduous shade with fall color and moderate water use.
• Texas ebony: evergreen, slow growing and tidy, though thorny.
• Thornless mesquite: fast desert shade, best kept away from walls and pools.

Costs and When to Call a Pro

Container trees range from modest prices for a 5-gallon size to several hundred dollars for a large boxed tree, with installation adding to boxed specimens. Professional pruning of a mature tree generally costs a few hundred dollars, and removal of a large multi-trunk tree near a pool or wall can run higher because of access and cleanup.

Hire a certified arborist for structural pruning on large trees, trees leaning after storms, or any work near power lines. If roots have damaged pool decking or plumbing, a pool contractor or licensed plumber should assess repairs before you cut major roots, since removing large roots can destabilize the tree.