stress detection

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The Potential of a Chlorophyll Content SPAD Meter to Quantify Nutrient Stress in Foliar Tissue of Sycamore (Acer pseudoplatanus), English Oak (Quercus robur), and European Beech (Fagus sylvatica)
Glynn C. Percival, Ian P. Keary and Kelly Noviss

Arboriculture & Urban Forestry (AUF) March 2008, 34 (2) 89-100; DOI: https://doi.org/10.48044/jauf.2008.012
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The Use of Chlorophyll Fluorescence to Identify Chemical and Environmental Stress in Leaf Tissue of Three Oak (Quercus) Species
Glynn C. Percival

Arboriculture & Urban Forestry (AUF) September 2005, 31 (5) 215-227; DOI: https://doi.org/10.48044/jauf.2005.028