Why pressure alone does not work
Sap is a sticky resin. It does not dissolve in cold water, and it bonds to the rough surface of concrete. A pressure washer can knock off a hardened blob, but the thin film underneath stays sticky. That sticky film then grabs dust and dirt, which is why sap spots turn into dark, gritty patches that look worse than the sap itself.
Turning up the pressure to force it off risks etching the concrete around the spot. The better approach is to change the sap first, either dissolving it with a solvent or softening it with heat, so it lets go with gentle cleaning.
Which trees cause it in LA
Pines are the classic sap trees, dropping sticky resin and pitch onto driveways and patios. Ficus trees, common as street trees and hedges in LA, drip a sticky residue and their fruit adds staining. Aphids and other insects on many trees produce honeydew, a sugary sap-like drip that coats cars and concrete and then turns black with sooty mold. Jacaranda blooms in late spring are a separate problem, with sticky purple flowers that stain. Our jacaranda guide covers that one in detail.
Knowing the source helps. Honeydew is sugar-based and comes off with hot water and detergent. Pine resin needs a solvent.
Method one: solvents and degreasers
For resin-type sap, apply a citrus-based degreaser or a product labeled for sap and tar removal. Mineral spirits also dissolve resin. Let it dwell a few minutes so it can soak into the sap, then scrub with a stiff nylon brush. The sap should turn gummy and lift. Wipe up as much as you can with rags before rinsing.
Follow with a detergent wash to remove the solvent residue, then rinse. Test any solvent on a hidden area first if your concrete is colored, stamped or sealed, because solvents can soften sealers. Wear gloves, keep flammable products away from heat and sparks, and dispose of oily rags safely.
Method two: heat and hot water
Heat softens sap. A hot water pressure washer is one of the most effective tools for sap and honeydew, because hot water loosens the bond while the spray rinses it away, with less need for strong solvents. Even without hot water equipment, pouring hot water from a kettle over a small spot and scrubbing immediately can help with sugary drips.
For thick, hardened pitch, scrape off the bulk with a plastic scraper first, then use heat or solvent on what is left. Do not use an open flame on concrete or near plants.
Mistakes to avoid
Do not grind sap into the surface with a wire brush. Steel bristles can leave rust marks, and grinding spreads the sap wider. Do not leave solvent-soaked sap to dry on hot Valley concrete, because it can re-harden as a stickier film. And do not rinse dissolved sap and solvent residue into the gutter. Los Angeles Municipal Code section 64.70.02 prohibits discharging untreated wash water from paved-surface washing into the storm drain system.
Finally, do not expect a perfect spot on old, porous concrete. Long-standing sap stains can leave a faint darker mark after the sticky film is gone, which usually fades as the slab weathers.
Prevention and when to get help
Trim branches that overhang the driveway where you can. Sweep and rinse fresh drips before they collect dirt, especially in summer when sap flows more. If honeydew is the problem, the tree may have an insect issue worth asking an arborist about.
Fresh drips are far easier than old ones. A sticky spot cleaned within days usually comes up with warm water and detergent. The same spot left for a season has collected layers of dirt and baked in the sun, and it takes solvent, dwell time and scrubbing to remove.
If sap covers a whole driveway or patio under a big tree, professional cleaning with hot water and pre-treatment saves a lot of scrubbing. As of October 2026, driveway cleaning is $0.50 per square foot and patio cleaning $0.65 per square foot on our calculator, with a $195 visit minimum and a flat price confirmed before work begins.
Key points
Why pressure alone does not work
Sap is a sticky resin. It does not dissolve in cold water, and it bonds to the rough surface of concrete. A pressure washer can knock off a hardened blob, but the thin film underneath stays sticky. That sticky film then grabs dust and dirt, which is why sap spots turn into dark, gritty patches that look worse than the sap itself.
Method one: solvents and degreasers
For resin-type sap, apply a citrus-based degreaser or a product labeled for sap and tar removal. Mineral spirits also dissolve resin. Let it dwell a few minutes so it can soak into the sap, then scrub with a stiff nylon brush. The sap should turn gummy and lift. Wipe up as much as you can with rags before rinsing.