Common Planting Mistakes

Our maintenance clients often call on us to fix landscaping and planting errors made by other contractors. Here is a case study of a recent landscapee rescue project we just completed.

Case Study – Poor Soil Preparation

Recently we’ve been reworking the planting in the front yard of a client whose has lost trees and shrubs due to a fungus named armillaria and compaction of soil.

Problem:

A large row of Texas Privet hedge and various shrubs were lost. The client desired these to be replaced as the Privet hedge offers them privacy against the street traffic. As that point, we tested the soil to determine the severity of the problem.

Planting and soil Poblem in Santa Barbara

Problem: Undetected Soil Fungus plus Irrigation and Electrical Conduits Not Buried Deep per Code Requirements

Diagnosis:

The causes of the problem was determined to be an undiscovered fungi in soil which caused root disease and poor planting techniques used by previous landscaper.

It is imperative that landscapers test the soil for harmful elements that can cause plant disease. An example of a harmful soil condition is Armillaria. A root disease commonly found throughout temperate and tropical regions of the world.

The disease has been reported in nearly every State. Hosts include hundreds of species of trees, shrubs, vines, and forbs growing in forests, along roadsides, and in cultivated areas. Fungi cause the root disease. They live as parasites on living host tissue or as saprophytes on dead woody material.

The fungus most often identified as causing the disease is Armillaria mellea. Recent research, however, suggests that several different but closely related species may be involved. Therefore, the generic term Armillaria is often used to refer to the entire classification of fungus. They live on coarse roots and the lower stems of conifers and broad-leaved trees.

As parasites, the fungi cause mortality, wood decay, and growth reduction. They infect and kill trees that have been already weakened by competition, other pests, or climatic factors. This type of activity occurs throughout the United States. The fungi also infect healthy trees, either killing them outright or predisposing them to attacks by other fungi or insects.

Prescription and Treatment

: Landscape After Solving Soil Problem

It is imperative that landscapers test for armillaria before planting. We immediately recognized the problem when we noticed the client’s plant material had symptoms of armillaria ….wilting and beginning to die. We addressed the problem in the following ways:

Choose a hedge that is naturally resistant to armillaria fungus. We paid close attention to the size of the holes dug for the plant material, as another reason the plants’ failure was that the previous contractor didn’t dig holes that were deep and wide enough to account for the expansion of the plants’ root system.
There was a lot of debris left in the soil: concrete, segments, rock, and asphalt. This is what caused the roots to become compacted. To solve this problem, all the contaminated soil removed, dumped and then replaced.
After removing the infected soil, we excavated a three-foot by two-foot wide continuous trench and imported light, well-drained soil around the root ball. We installed two inches of gravel for drainage and planted the root ball two inches above grade for proper drainage.