Ahhh....suburban (and urban) soils. Alas, they are the cause of many tree problems including nutrient deficiencies!
Think about it...in a natural or forested environment, soil is rich in organic matter because everything that falls to the ground stays there, decomposes, and adds nutrient goodness over time. But here we are being responsible homeowners and raking away all that debris! Not to mention when our houses were built, the soil was likely disturbed in a major way. The natural layers were disrupted and the pore spaces meant for oxygen and water were compacted down by equipment. It's no surprise that many trees in suburban and urban areas struggle!
What are the symptoms of a nutrient deficiency? Easy - yellow leaves, usually with dark green veins, and early leaf drop.
What's the big deal anyway?!
Nutrient deficiency can be a factor that at a minimum, causes stress which can predispose a tree to pest & disease problems. Often the problem is not that the nutrient is in low supply, but that the soil pH (generally too alkaline) has made it unavailable for the tree to use. The amount of rich organic matter also affects the ability of soil to hold onto nutrients. Soil testing can help shed light on what's going on beneath the surface.
Solutions, solutions, my oh my...It takes a VERY long time to change soil pH due to the soil's amazing ability to buffer pH. (Most trees prefer slightly acidic soil). Direct trunk injection of the lacking nutrient is often a good option. But the best option of all is to test your soil before planting!
In our area, we often see iron deficiency in pin oaks and manganese deficiency in red maples.
Loggin' off for now,
ISA Certified Arborist #IN-3457A
P.S. Gotta have a little tree pun fun! Ok, what type of tree fits in your hand? A PALM tree, of course!