Common Tree Diseases in Rhode Island and How to Spot Them

Trees are a vital part of any landscape—but like any living thing, they can get sick. In Rhode Island, certain tree diseases are more common due to our climate, tree species, and seasonal changes. If left untreated, these issues can spread quickly and lead to dangerous structural damage or even total tree failure.

Here’s what homeowners and property managers need to know to protect their trees—and when it’s time to call in the pros.

Our state's humid summers, wet springs, and long winters create the perfect environment for fungal infections, insect infestations, and decay. Left unaddressed, diseased trees:

• Can become unstable or drop limbs
• May infect neighboring healthy trees
• Pose risks to your home, power lines, or vehicles

Early detection is your best defense.

Anthracnose

Anthracnose is a fungal disease that commonly affects maples, oaks, and sycamores in Rhode Island, especially during the wet, cool conditions of spring. Infected trees typically show brown or black blotches on their leaves, and may begin to drop leaves prematurely. You may also notice twigs dying back or thinning out near the canopy. If left untreated, anthracnose can weaken a tree significantly over time.

Dutch Elm Disease

A devastating issue for American elms, Dutch Elm Disease has wiped out countless historic trees across the Northeast. It spreads through bark beetles and root grafts, causing symptoms like yellowing and wilting leaves, followed by branch dieback from the top down. Infected elms can decline rapidly, and once the disease takes hold, it is often fatal.

Canker Diseases

Canker diseases affect a wide range of trees including birch, beech, maple, and ash. These infections usually appear in trees that are already stressed from drought, storm damage, or construction impact. Look for sunken or dead patches on the bark, sap oozing from wounds, or bark that appears to be splitting. Over time, the disease can lead to a gradual die-off of branches and significant structural weakening.

Apple Scab

Although it most commonly affects crabapple trees, apple scab is a fungal disease that can tarnish the appearance and health of any ornamental apple species. The disease causes olive-green to black spots on leaves and fruit, often leading to early leaf drop in late spring. While rarely fatal, repeated infections weaken trees and make them more susceptible to other problems.

Verticillium Wilt

Verticillium wilt is a soil-borne fungus that affects maples, ash, redbuds, and several other popular trees in Rhode Island. The disease can lie dormant in the soil for years before symptoms emerge. Infected trees often display wilting on one side of the canopy, yellowing between the leaf veins, and dark streaks under the bark. Once it spreads through the vascular system of a tree, recovery becomes difficult without professional intervention.

How to Spot the Signs of Tree Disease Early

Common red flags include:

• Patchy or premature leaf loss
• Cracking or oozing bark
• Fungus growing on the trunk or branches
• Dead branches in the upper canopy
• Unusual insect activity

If you notice any of these signs, your tree may already be infected.

While it may be tempting to wait or manage the issue yourself, misdiagnosing or delaying treatment can make the problem worse. A certified arborist can:

• Identify the disease accurately
• Recommend the right treatment or safe removal
• Prevent spread to nearby trees

Some cases can be treated, but others may require full tree removal to protect your home and landscape.

M&M Tree Service provides tree inspections, disease identification, and removal services across Rhode Island. We serve homeowners and property managers in Warwick, Cranston, Smithfield, and surrounding communities.

Our experienced team knows the signs of every major tree disease common in this region—and we know how to handle them safely and effectively.

Think your tree might be sick? Don’t wait until it becomes a hazard. Our Rhode Island-based team can assess your tree’s condition and offer practical solutions on the spot.

Call M&M Tree Service today to schedule a free disease inspection anywhere in Rhode Island.