Tree health assessment

Tree Health Assessment

In addition to increasing threats from pests, diseases and other issues, trees, particularly in altered and built environments, are often affected by compacted soils, limited space for root growth, lack of water, poor soil quality, among many other factors.

This can result in a deterioration in tree health, particularly following changes in the rooting environment after construction works or other changes close to trees.

Many tree health problems start in the soil. A healthy soil is not an inert growing medium but is full of living organisms. These range from ‘large’ organisms such as worms which have a huge influence on soil structure and organic matter turnover, down to microscopic organisms, some of which have a symbiotic, or mutually beneficial relationship with tree roots. Many soils, particularly damaged, altered or imported soils, lack these organisms, have poor soil structure, have pH or nutritional levels incompatible with healthy tree growth, or other issues.

Chlorophyll Fluorescence

We can tell a lot about tree health from a visual assessment, but we can also test trees for stress before symptoms show visually. We use Arborcheck chlorophyll fluorescence instruments to assess tree vitality.

Results can indicate many forms of stress long before visual indicators, such as leaf colour change, early leaf fall, increasing dieback and deadwood etc., are evident.

Physiological stress caused, for example, by drought, nutrient deficiencies, chemical damage, root loss or damage, can be detected early, allowing remedial measures to be taken if appropriate.

Chlorophyll fluorescence testing has many applications, key uses being:

Testing of trees pre-and post-development

Damage caused to trees from soil compaction and root damage often does not manifest itself for some time after completion of works. Monitoring can be used to demonstrate the effectiveness of tree protection measures.

Legal issues

Suspected or alleged damage to trees can take a long time to be obvious from visual assessment. Arborcheck can detect the early stages of decline and be used to gather evidence where required.

Monitoring of damaged trees or those affected by pathogens

Where a tree is known to have been damaged or has symptoms of a disease, monitoring can be used to evaluate how this is affecting the tree's health.

Monitoring the efficacy of treatments

Various treatments are available for trees known or suspected of suffering damage, whether from compaction, root damage, disease, or other factors. In addition to allowing for very early recognition of stress factors, Arborcheck can be used to test whether treatments have been successful.

Selection and testing of new planting stock

Arborcheck allows trees to be tested (when in leaf) prior to purchase to ensure that the vitality of the tree is sound from a physiological stand point in addition to a visual perspective.

The first few years post-planting are critical for a young tree to achieve independence within the landscape. In addition to stock with poor physiological condition, trees can fail for a variety of reasons including inadequate planting or poor routine maintenance.

The recent British Standard BS 8545 Trees: from nursery to independence in the landscape – Recommendations, describes the use of chlorophyll fluorescence and chlorophyll content measurements as tests that “should be carried out wherever practicable”. Arborcheck can help to highlight abnormal decline in tree vitality post-planting so that remedial work may be carried out before the tree becomes a costly re-planting exercise.

The Arborcheck system has been developed in collaboration with Bartlett Tree Research Laboratories and Barcham Trees.

The techniques used in testing have strong grounding in peer-reviewed scientific publications.

Leaf Tissue Testing

Leaf tissue testing can be used to to give an accurate analysis of nutrient content and deficiencies, to identify appropriate interventions.

Soil Testing

Soil analysis to assess compaction and penetrability and soil health can be carried out to allow for the appropriate recommendations made to improve the health of an individual tree or a tree population, or in advance of new tree planting. This can include testing for soil nutrients, microbial identification, and physical and structural soil assessment.

Where an issue has been identified, recommendations to remediate may be made. This may include soil decompaction, the use of woodchip incorporated into the soil or used as a mulch, the addition of biochar, compost tea, or other ameliorants.  We work alongside specialist contractors and recommendations will be bespoke to the particular tree or situation.