What Is Chlorosis?
Chlorosis is a condition where tree leaves turn yellow, usually between the veins while the veins themselves stay green. It's caused by a deficiency of iron, manganese, or other micronutrients that the tree needs to produce chlorophyll, the green pigment that powers photosynthesis.
Chlorosis is extremely common in Central Iowa. The culprit is usually our soil, not a lack of nutrients in the ground. Iowa soils tend to be alkaline (high pH), which locks up iron and manganese so trees can't absorb them, even when those nutrients are present in the soil.
Don't waste money on store-bought iron stakes or soil amendments. If your soil pH is the problem (which it usually is), adding iron to the soil won't help, the tree still can't absorb it. Trunk injection bypasses the soil entirely and delivers nutrients directly where they're needed.
Trees Most Affected by Chlorosis in Iowa
Some species are much more susceptible to chlorosis in Iowa soils than others. If you have any of these trees and notice yellowing, chlorosis should be on your list of suspects:
- Pin oak: the most commonly chlorotic tree in Iowa; pin oaks are notorious for struggling in alkaline Midwestern soils
- River birch: highly susceptible to iron chlorosis
- Silver maple
- Sweet gum
- Red maple
- Magnolia
- White oak
What Happens If Chlorosis Goes Untreated
A mildly chlorotic tree looks unsightly but may survive for years. However, prolonged chlorosis weakens the tree significantly:
- Reduced photosynthesis means the tree produces less energy for growth and defense
- Weakened trees are more susceptible to secondary pests and diseases
- Severe or repeated chlorosis causes branch dieback, starting at the tips
- In extreme cases, chronic nutrient deficiency kills the tree over several seasons
Our Treatment: Mn-Jet Fe Trunk Injection
At Emma Joe's Tree Service, we use Mn-jet Fe, a professional-grade iron and manganese product injected directly into the tree by our state certified and Arborjet certified applicators. This completely bypasses the soil pH problem and delivers nutrients straight into the tree's vascular system.
How It Works
- Injection is done in the fall as the tree begins storing nutrients for the following spring
- The tree absorbs the Mn-jet Fe into its vascular system, where it's used directly for chlorophyll production
- Most treated trees show dramatic improvement by the following growing season - noticeably greener, healthier foliage
- Treatment needs to be repeated every 2–3 years as the tree uses its supply
Shortstop Growth Regulator: The Perfect Complement
We combine Mn-jet Fe injections with our Shortstop plant growth regulator treatment. Shortstop (paclobutrazol) is a soil-injected product that redirects the tree's energy from top growth toward root development and nutrient uptake, making the tree more efficient at absorbing and using the nutrients we deliver.
The two products work incredibly well together. Apply Shortstop to the soil, inject Mn-jet Fe in the fall, and by the following spring you'll see a transformed tree. Mn-jet Fe is our most affordable plant health care product, and it comes packaged with the Shortstop treatment.
Best timing: We apply the Shortstop growth regulator anytime the ground isn't frozen, and the Mn-jet Fe injection in the fall. If your tree is showing symptoms now, call us so we can get it on the schedule.
Diagnosing vs. Assuming
While chlorosis is common, yellow leaves can also be caused by other conditions, waterlogged soil, girdling roots, certain diseases, or even normal seasonal change. We're happy to assess your tree and confirm the diagnosis before recommending treatment. No guessing, no spraying and hoping for the best.
Service Area
We provide chlorosis treatment throughout Central Iowa, Roland, Story City, Ames, Boone, Nevada, Huxley, Ankeny, Gilbert, and surrounding areas in Story, Boone, Hamilton, and Polk counties.