Show #125 - Why Trees Fail: The Hidden Cost of Starvation

Many neighborhoods wait until trees are already failing before calling professionals. By that point, thinning canopies, early leaf drop, and gray or blackened trunks signal years of decline—not sudden disease.

While issues like drought, bacteria, and pests may contribute, the number one cause of tree failure is lack of food.

Trees are living systems. Water alone is not enough.

The Most Common Tree Decline Symptoms

• Thinning or sparse canopies
• Early seasonal leaf drop
• Ashen, gray, or burnt-looking bark
• Dull trunk coloration
• Exposed or harsh surface roots
• Poor recovery after pruning

An ashen or scorched trunk appearance is often a critical warning sign of advanced decline.

Why Trees Starve in Neighborhoods

• Trees away from lawns never get fertilized
• Lawn-fed trees survive only by accident
• Many trees go 20–40 years unfed
• Soil erosion worsens without nutrients
• Roots stay shallow searching for food

A single 20” caliper oak can move one ton of water per day, yet without fertilizer, even ample rainfall cannot save it.

The Role of Fertilizer in Tree Health

Trees require proportionate nutrition, not just water.

• Fertilizer feeds soil biology
• Roots follow nutrients deeper into soil
• Proper feeding reduces erosion
• Trees heal pruning wounds faster
• Growth rings reflect yearly nutrition

Without food, trees slowly decline over 4–6 years.

Proper Tree Feeding and Mulching

How to Feed Trees Correctly

• Apply fertilizer 1” away from trunk
• Extend feeding zone 2–4’ outward
• Match fertilizer volume to tree size
• Feed trees directly, not indirectly

Mulching Essentials

• Use shredded hardwood bark mulch
• Minimum 2–3’ mulch circle
• Expand mulch as tree grows
• Mulch should touch trunk
• Maintain 3” mulch depth

Mulch helps trees retain water, regulate temperature, and protect roots.

Treating Ashen or Burnt Tree Bark

To address ashen trunk appearance:

• Mix 4 oz Monterey Agri-Fos
• Add 4–6 oz Wilt-Pruf
• Combine with 1 gallon warm water
• Apply to affected bark surfaces

Tree wounds under 12” should heal within one year when nutrition is restored.

Recommended Tree Fertilizers

Use high-quality, low-salt fertilizers:

• Plant Trust 21-5-12
• Fertilome Start-N-Grow 19-6-12
• Anderson’s 18-6-12
• ShowTurf with IBDU 28-0-8

Avoid These Fertilizers

• 10-10-10 and 10-6-4
• Scotts products
• Miracle-Gro
• Jobes Tree Spikes

Low-grade fertilizers cost more per pound of usable nitrogen and damage soil life.

This Week in the Garden

• Remove leaf litter from lawns
• Use mower to vacuum debris
• Compost organic materials
• Evaluate lawn color for nutrition
• Fertilize lawns and trees
• Apply lime: 40 lbs per 1,000 sq ft
• Use Preferential Treatment fertilizer
• Spray deciduous wood for pests
• Mulch broadleaf plants properly

Focus spraying on fruit trees, lilac, roses, and flowering deciduous shrubs.

Final Thoughts

Trees are long-term investments that grow in value—from $100 to over $20,000. They clean our air, anchor our communities, and support wildlife.

If you want healthy trees tomorrow, feed them today.

There are no great gardeners without great food.