Black Spots on Maple Leaves: What Causes Them?

By the YardClues editorial team · Updated

Black spots on maple leaves are most often caused by tar spot, a very common fungus that makes raised, shiny, tar-black spots about 1/2 inch across by late summer and fall. It looks alarming but is largely cosmetic, and the main fix is simply raking up and removing the fallen leaves this fall. If the black is a wipe-off film, irregular blotches along the veins, or crispy edges instead, you're more likely looking at sooty mold, anthracnose, or leaf scorch.

Most likely causes

  • Tar spot — raised, shiny black spots 1/2 inch or larger, often with a yellow halo
  • Speckled tar spot — clusters of many pinhead-size black dots
  • Maple anthracnose — irregular brown-to-black blotches along and between the veins after a wet spring
  • Sooty mold — black, powdery film that wipes off with a damp cloth
  • Leaf scorch — brown-to-black, crispy edges and tips during heat and drought

Not quite what you're seeing? Answer four quick questions and the clue finder will point you to a closer match.

Compare the possible causes

Possible cause Key signs When it happens How likely
Tar spot (Rhytisma acerinum) Raised, shiny, tar-black spots about 1/2 inch or more across, often ringed with a yellow halo; looks like drops of tar on the leaf Starts as small yellow-green spots in early summer; turns black and obvious by late summer and fall Very common
Speckled tar spot (Rhytisma punctatum) Clusters of many tiny, pinhead-size black dots grouped together instead of one large blotch Most visible in late summer and fall Common
Maple anthracnose Irregular brown-to-black blotches that follow the veins or spread between them; leaves may curl or look scorched Late spring into summer, following cool, wet springs Common
Sooty mold A black, powdery or sooty film coating the leaf surface that wipes off with a damp cloth; leaves or anything below may feel sticky Summer into fall, wherever sap-feeding insects are active Common
Leaf scorch Brown-to-black, dry, crispy leaf edges and tips, with the center of the leaf staying green Mid to late summer during heat and drought Common
Phyllosticta leaf spot (purple-eye) Small tan spots with purple-brown borders; the centers may dry and drop out Late spring and summer Less common

Visual clues to check

  • Run a finger over a spot: raised, shiny, tar-like black patches 1/2 inch or larger point to tar spot
  • Look for a yellow ring around each black spot — a classic tar spot sign
  • Check for clusters of tiny pinhead dots instead of one big blotch: that's speckled tar spot
  • Wipe the leaf with a damp paper towel: if the black comes off, it's sooty mold, not a leaf disease
  • Look at the underside of leaves and twigs for aphids, scale, or spotted lanternflies if you find sooty mold or sticky residue
  • Follow the veins: irregular brown-to-black blotches along and between them suggest anthracnose
  • Check the leaf edges: dark, crispy margins with green centers during dry weather mean scorch
  • Note the tree type: Norway maples are the most frequent tar spot hosts

The causes in detail

Tar spot (Rhytisma acerinum)

Tar spot is the most likely answer to what causes black spots on maple leaves, especially on Norway maples, though red and silver maples get it too. The fungus spends the winter on fallen leaves and releases spores that infect the new leaves in spring during wet weather — which is why some trees seem to have it every year. Heavily spotted leaves may drop a little early, but the tree's health is rarely affected. Raking up and removing fallen leaves each fall is the most effective step you can take.

Speckled tar spot (Rhytisma punctatum)

This is a close cousin of tar spot that peppers the leaf with fine black specks rather than forming a single tarry patch. It's equally cosmetic, and the same fall cleanup of fallen leaves reduces it the following year. No other treatment is needed.

Maple anthracnose

Anthracnose spots are flat and irregular rather than raised and round, and they tend to track along the leaf veins. In a rainy year it can cause noticeable early leaf drop, which is unsettling to watch in midsummer. Trees usually leaf out normally the next spring, and improving airflow and removing fallen leaves helps.

Sooty mold

Sooty mold isn't attacking the leaf — it's a fungus growing on honeydew, the sugary liquid dripped by aphids, scale insects, or spotted lanternflies feeding above. The wipe test is the giveaway: tar spot won't budge, sooty mold smears off. Deal with the insect, and the mold fades away on its own.

Leaf scorch

Scorch happens when a tree can't move water to its leaves fast enough, so the outer edges dry out first. It's most common on young or stressed trees and on maples planted near driveways, streets, and other pavement that radiate heat. Deep watering during dry spells and a ring of mulch are the best prevention.

Phyllosticta leaf spot (purple-eye)

These spots look more tan and purple than black up close, but they can read as dark specks from a distance. It's a minor leaf spot that doesn't threaten the tree and doesn't call for treatment beyond normal leaf cleanup.

When to worry

  • Large limbs are dying back or the canopy is thinning noticeably year after year
  • The tree drops most of its leaves in early summer for several years running
  • Sooty mold keeps coming back, signaling a heavy, ongoing insect infestation — especially spotted lanternflies
  • A young or newly planted maple shows severe scorch along with wilting during drought

What to do now

  1. Rake up fallen maple leaves this fall and bag them or add them to a hot compost pile to cut down next spring's infection
  2. Water deeply during dry spells, especially young trees and maples near pavement
  3. Spread 2–3 inches of mulch over the root zone, keeping it pulled back a few inches from the trunk
  4. If branches are crowded, prune to open the canopy so leaves dry faster after rain
  5. If you find sooty mold, identify and address the sap-feeding insect causing the honeydew
  6. Call a certified arborist if large limbs are dying back or the canopy thins year after year

What not to do

  • Don't spray fungicides on large maples for tar spot — it isn't needed for mature landscape trees
  • Don't toss infected leaves in a cold compost pile you'll later spread under the same trees
  • Don't leave infected leaves lying under the tree through winter if you want fewer spots next year
  • Don't panic over tar spot — it's cosmetic and rarely affects the tree's health

Frequently asked questions

What causes black spots on maple leaves?

The most common cause is tar spot, a fungus that creates raised, shiny black spots about 1/2 inch across, often with a yellow halo, by late summer and fall. Less often, the black is sooty mold growing on insect honeydew, maple anthracnose after a wet spring, or scorched leaf edges from heat and drought. Rubbing or wiping a spot and checking where it sits on the leaf usually tells you which one you have.

Is tar spot killing my maple tree?

Almost certainly not. Tar spot is largely cosmetic — heavily spotted leaves may fall a little early, but the tree's health is rarely affected. If you're also seeing large dead limbs or a thinning canopy year after year, that's a separate problem worth having an arborist look at.

How do I get rid of tar spot on maple leaves?

Rake up the fallen leaves in fall and remove them by bagging or adding them to a hot compost pile. The fungus overwinters on dead leaves and reinfects new ones in spring during wet weather, so cleanup breaks the cycle. Fungicide sprays aren't needed for mature landscape trees.

Why do my maple leaves have a black coating that wipes off?

A black film that wipes off is sooty mold, a fungus growing on honeydew dripped by aphids, scale insects, or spotted lanternflies. It doesn't infect the leaf itself. Find and manage the insect, and the sooty mold disappears on its own.

Will my maple have black spots again next year?

It may, especially after a wet spring, because tar spot spores come from last year's fallen leaves. Removing fallen leaves from under the tree — and encouraging neighbors to do the same — reduces the amount of fungus around next spring. Some spotting may still appear, but it remains cosmetic.

Related yard clues

Plant Damage Yellow Leaves With Brown Spots: Disease, Mites, or Aging? Yellow leaves with brown spots are most often a fungal leaf spot disease, early blight (on tomatoes, with its bullseye-ringed spots), bacterial spot, or spider mite feeding that starts as fine pale stippling. A few yellowing lower leaves on an otherwise healthy plant, though, are usually just natural aging. Where the spots sit, their shape, and whether they have rings or halos point to the cause. Read the guide → Plant Damage Sticky Residue on Leaves: Honeydew and What's Making It A sticky, shiny film on leaves is honeydew — the sugary waste excreted by sap-sucking insects like aphids, soft scale, whiteflies, or mealybugs feeding somewhere above the sticky spot. Look up and check leaf undersides to find the source, and don't be surprised if ants are patrolling the plant: they farm these insects for the honeydew. Read the guide → Plant Damage Why Is My Tree Dripping Sap? Sticky Ooze Explained A tree dripping sticky liquid is often not leaking true sap at all — it's usually honeydew, the sugary waste of aphids, scale, or lanternflies feeding in the branches above. Real sap does flow from pruning cuts and storm cracks, and darker, foul-smelling ooze can be bacterial slime flux. Checking the leaves above the drip and the smell of the ooze usually points to the cause. Read the guide → Plant Damage White Spots on Tree Bark: Lichen, Bugs, or Mildew? White or grayish patches on tree bark are most often lichen — a harmless organism that simply perches on the bark and is not a disease or parasite. The other common causes are cottony white scale or woolly aphids, powdery mildew on green bark and leaves, or deliberately whitewashed trunks. Whether the growth is crusty, cottony, or powdery tells you which one, and lichen itself never needs treatment. Read the guide →

Still not sure? Compare with these clues

Bugs & Eggs Spotted Lanternfly: Egg Masses, Nymphs & Adults A gray, putty-like smear that looks like dried mud on a trunk, rock, or furniture is very likely a spotted lanternfly egg mass — and if you're seeing the insect itself, the black-and-white or red white-spotted nymphs (spring to summer) and gray spotted-winged adults (late summer) belong to the same pest. Spotted lanternfly is a highly invasive species under quarantine in many eastern states, so the right move at any stage is to confirm the ID, destroy what you find, and report the sighting rather than ignore or move it. Read the guide → Mushrooms & Growths Shelf Fungus on a Tree Trunk: A Sign of Decay Inside the Tree A shelf or bracket fungus growing from a living tree's trunk is a red flag: it means the fungus has been decaying wood inside the tree, often for years, before producing that visible 'conk.' The tree may still look healthy, but internal decay weakens its structure — so the right move is an assessment by an ISA-certified arborist, not knocking the fungus off. Read the guide →