Olson Tree Care in Des Moines, Iowa has found that Foliar Analysis gives you the facts.
While in Des Moines, Iowa farmers mainly use laboratory analysis for nutrient content of plants, many Des Moines Arborists have found it to be an amazing resource. Without tissue testing it becomes a guessing game, that often makes the best Des Moines Tree Services throw stuff at the tree to see if it works.
Case in point...
Customer calls for Tree Health Evaluation of a black alder (Alnus glutinosa) that wilted and looks near dead after having been somewhat healthy last year. Visual analysis led the Des Moines Arborist at Olson Tree Care to 2 areas... abiotic (toxicity) and biotic (pathogen such as Phytophthora alni.) With treatment options costly for Phytophthora we did not want to go in that direction without ruling out nutrient toxicity. So...... for a small fee we sent a tissue sample to a lab.
The results came back high in boron, copper, iron, sulfur, magnesium with calcium and nitrogen excessively high. Testing found the culprit and provided an exact diagnosis. Turns out the neighbor had burned the lawn with fertilizer in spring right on the property line over the root zone of the tree. Leaching was recommended before results had come in on this case.
Standard levels for similar species