Are Your Trees Looking Yellow?
If you answered yes, your tree may be experiencing chlorosis. Symptoms of chlorosis is yellowing leaves with dark green veins, typically due to nutrient deficiencies, like iron and manganese. *Drought stress is a catalyst*
The effect on trees:
- Weak/brittle growth
- Poor to no Fall leaf color (iron and manganese are what provide the red colors that trees are prized for)
- Reduced life span
Causes of chlorosis:
- High soil pH of 7.0 and above
- Irrigation of lawns cause carbonates to build in soil, exacerbating the issue.
- Lawn fertilization with high phosphorous
- Lawn fertilization with high pH levels
Chlorosis Mitigation
To improve the health of chlorotic trees, the first action recommended is to ensure proper root zone irrigation. Severe chlorosis symptoms include extremely yellow leaves, leaf burning, and leaf drop. Mitigation with those symptoms is necessary to stop risk of canopy decline and imminent structural damage.
Standard Protocol for a Chlorotic Tree Is:
- Fall or Dormant Season trunk injection of iron and Plant Growth Regulator application.
- Seasonal Fall and Spring tree root zone soil amendment and fertilization.
- Maintain root zone irrigation during dormant season.
- Monitor the tree in late May/June once leaves have hardened, to view the effect of applications.
What is going on if the tree still has chlorotic symptoms after this protocol?
Other issues that can cause compound chlorosis symptoms are:
- Encircling roots or girdling – which cannot be seen without root collar excavation.
- Root zone compaction
- Soil chemistry (pH level specifically)
What other options are there for mitigation or more intensive protocols?
Further Intensive Chlorosis Mitigation Protocols:
- Soil testing -data for further product applications acutely as needed.
- Air spading – root collar excavation (pruning roots), remediating/amending soil and root zone decompaction with vertical or radial trenching.
- Seasonal (Fall and Spring) soil injection chemistry amendment/fertilization
- Foliar nutrient application (Summer Green Up)
Schedule a consultation with us for chlorosis mitigation!
For additional information and resources on amending your soil for root zone health, check out this helpful DIY YouTube video:
We’ve Changed How We’re Treating Yellowing Foliage and It’s Working! 
// Garden Answer
And in case you missed it, check out our “How To Water Your Tree Like a Professional” page, located here: Watering Trees – Earth to Sky llc TREES!