The worst plant diseases in your Idaho backyard sound bad enough.
You wouldn’t want to face down “Rhizosphaera Needle Cast” in a spelling bee. But can you spot it on your plants?
Table of Contents
- The Most Common Plant Diseases in Idaho
- What Are the Signs of Diseased or Damaged Plants?
- If Your Plants Are Sick, Is It Too Late to Save Them?
- Not Dead Yet? How Plant Health Care Can Help
- What Are the Best Ways to Prevent Shrub Disease?
- Keep Your Trees and Shrubs Thriving with Lawn Buddies
What are the most common plant diseases in Idaho? Marssonina Leaf Spot. Rhizosphaera Needle Cast. Powdery Mildew. Fire Blight.
Encountering these diseases could be trouble for your landscape. Thankfully, there are ways to recover from (and prevent) common plant diseases in Idaho.
The Most Common Plant Diseases in Idaho
Let’s learn more about diseases that affect shrubs and trees, and how to treat and prevent them.
1. Marssonina Leaf Spot
This is a fungal disease that strikes aspen, poplar and cottonwood trees — among the most common trees here in Idaho.
It shows up on the leaves as brown spots with yellow halos. The spots gradually merge together, forming large brown blotches. The leaves often fall off the trees earlier than usual.
This plant disease doesn't usually kill trees, but it does weaken them over time and cause stress.
2. Rhizosphaera Needle Cast
This fungal disease affects spruce trees, especially Colorado blue spruce, causing their needles to turn yellow, then brown and eventually they fall off.
Trees stressed from drought or poor planting are more likely to suffer from it.
3. Powdery Mildew
This one looks just like it sounds. You’ll notice gray or white-ish powdery blotches forming on your tree or shrub’s leaves that look like mats of fuzzy felt.
Here in Idaho, this fungal disease commonly affects maple, oak, dogwood, crabapple, magnolia and catalpa trees.
4. Fire Blight
If this sounds bad, you’re right. This bacterial disease is super destructive, and typically strikes apple and pear trees.
It can kill a tree’s blossoms, fruit, shoots, twigs, branches and entire trees.
Fire blight starts as cankers in the tree’s tissue, quietly lingering over the winter. Then, once the tree blooms in the spring, the infection spreads as the bacteria are carried from the cankers to the vulnerable open flowers by splashing rain, pollinating insects or during pruning.
5. Iron Chlorosis
Iron chlorosis isn’t a disease, exactly; it’s a nutrient deficiency, but we’re including it here because it’s a condition that often affects our beautiful maple and aspen trees here in Idaho, and plant health care can help.
It happens when trees can’t absorb all the nutrients they need from the soil. Trees with iron chlorosis have yellowing leaves that never quite get green.
What Are the Signs of Diseased or Damaged Plants?
You can usually tell if things aren’t going great out there for your shrubs and trees.
What are the signs of unhealthy shrubs and ornamental trees?
- Leaves that are pale, yellowing, brown or have unsightly splotches
- Leaves that drop much earlier than normal
- Wilting or curling leaves
- Thin foliage or bare branches
- Deep cracks or splits in the trunk
- Bark that’s falling off or loose
- Oozing sap
- Mushrooms growing on the trunk or base, which can signal rot
- Brittle, leafless branches that snap easily
- Branches that fall unexpectedly
If Your Plants Are Sick, Is It Too Late to Save Them?
It depends. If you catch an Idaho shrub disease early enough, it can often be cured with the right diagnosis and plant health care.
But if there are no signs of life, you might need to start over with a new tree or shrub.
How do you know if your shrub is dead?
Choose a branch and scratch off a bit of the outer bark. If you see green, there’s some life left.
No luck? Try another branch, closer to the roots. If you can’t reveal any green, sorry, it’s dead.
You can also bend a few branches of your shrub to see if they’re flexible. If all you get are snapping noises as branches break off, your shrub is likely dead.
Not Dead Yet? How Plant Health Care Can Help Cure Diseases
Don’t leave your diseased tree or shrub on its own to battle an invasive disease. Skilled plant health care in Idaho Falls can often bring a sick plant back to health.
Sometimes a heavy dose of fertilizer can nurse a tree back to health. A fungicide can often zap the infecting spores.
The good news? There are ways to deliver fast, effective treatment for ailing trees and shrubs:
Fungicides
Fungicides kill or prevent the growth of fungal diseases such as blights and mildews.
How do they work? A couple of different ways:
Contact fungicides are preventive, applied to the exterior of the tree or shrub. They remain on the plant and work by killing spores on the surface or by blocking their germination. Applying them in late winter or early spring, before trees and shrubs start growing, can help prevent common plant diseases.
Systemic fungicides are absorbed by the plant and move into the tissues, stopping diseases that have already started.
Tree Injections
Tree injections are like shots for your trees. They treat diseases and insects by delivering treatment directly into the tree trunk, which is quickly taken up by the vascular system and distributed throughout the tree.
This direct treatment works faster and is more effective than spray treatments.
Here at Lawn Buddies, we often use tree injections to treat fire blight and for maple trees suffering from iron chlorosis.
Tree injections deliver micronutrients directly into the stressed tree and quickly replenish its nutrient levels.
While other treatments typically require 3 to 4 treatments, tree injections require only 1 and last for a full year.
Deep Root Tree Fertilization
How to get nurturing nutrients to your stressed tree ASAP? Go straight to its roots.
Deep-root tree fertilization injects nutrients directly into your stressed tree's roots, rather than spreading them on the surface.
By injecting fertilizer under high pressure, nutrients like phosphorus and iron can reach the deepest tree roots quickly, feeding your tree from the roots up. Your ailing tree gets an immediate nutrition boost.
Over time, the nutrients move to the rest of your tree, making it healthier and more vibrant.
What Are the Best Ways to Prevent Shrub Disease?
Plant health care, such as fungicides and tree injections, can treat plant diseases, but preventing them in the first place is even better.
Here’s how:
First, Plant Your Trees and Shrubs With Care
It’s really important to plant your tree or shrub in a spot where it will thrive.
Check the instructions on the planting tag. Does it need full sun, or prefer partial shade? Will it need a windbreak from the icy Idaho winter wind?
Once you know it will like where it’s planted, settle your new tree or shrub in at the proper depth.
It’s pretty common to plant a tree too deeply. Follow the planting instructions on the tag. If you plant it too deeply, your tree can suffer from root rot, develop a thinning canopy, or be susceptible to cankers. None of this is good.
What are the best ways to prevent shrub disease? Your tree or shrub’s good health starts from the very beginning, when you sink it into the ground at its new home.
Prune Properly
Proper pruning techniques play a huge role in preventing diseases in your Idaho trees and shrubs.
How? A few key ways:
- Pruning out diseased branches keeps fungus from spreading to healthy parts of the tree or shrub.
- Thinning crowded branches allows air to circulate, reducing the moisture that fungus and bacteria need to thrive.
- Pruning allows more sunlight to reach the interior of your tree or shrub, killing disease-causing organisms and promoting important photosynthesis, which boosts your tree or shrub’s ability to resist common plant diseases.
Removing weak branches encourages stronger growth, so your tree or shrub can stand up to stress like plant diseases.
Prune at the Right Time — Winter
Your trees and shrubs are dormant in winter, so you’ll do less damage when you make those pruning cuts in winter than if you tackle this task when they’re actively growing.
Fresh pruning cuts attract insects, which can carry diseases. Winter means no pesky insects to invade while your pruning cuts heal.
Pro tip: if your pruning includes trimming out infected areas of your tree or shrub, disinfect your pruners between cuts. Otherwise, you’ll help spread the disease.
Dispose of Infected Leaves
The fungi and bacteria that cause tree and shrub diseases hang out in their fallen leaves and twigs and can spread the infection to other plants.
So keep any infected leaves cleaned up and disposed of.
Keep Leaves Dry
Wet foliage encourages disease, so avoid overhead watering that soaks the leaves. Water early in the day so leaves can dry, or use soaker hoses or drip irrigation that focus watering at the roots.
Keep Your Trees and Shrubs Thriving with Lawn Buddies
Worried about a sick tree or shrub? Come to the rescue with plant health care that works fast.
A good plant health care program is your tree or shrub’s best friend, offering food and fixes for every problem. Get your plant pride back with the best Idaho Falls plant health care services.
Expert plant health care is available for our Idaho Falls customers who use our full-service lawn care program.
The first step is to sign up for our 6-step complete lawn care program.
You’ll be glad you did.
Choose an Idaho Falls professional lawn care service that makes it easy, bundling your yard’s most-needed treatments into one convenient, no-fuss plan.
Got a few minutes? That’s all you need to get started. Just fill out the form on this page, call us at (208) 656-9131 or read more about our services. Then you can kick back and relax in your healthy, thriving yard.
Image Sources | Marssonina Leaf Spot, Fire Blight, Iron Chlorosis
