%0 Article
%T The use of needle colour in predicting growth and response to fertilization
%A Luukkanen, Olavi
%A Räsänen, Pentti K.
%A Yli-Vakkuri, Paavo
%D 1971
%J Silva Fennica
%V 5
%N 4
%R doi:10.14214/sf.a14655
%U https://silvafennica.fi/article/4853
%X <p>About 4,000 seedlings of Scots pine (<em>Pinus sylvestris</em> L.) and Norway spruce (<em>Picea abies (</em>L.) H. Karst.) were planted in 1965 both on a clear-cut and sheltered area in Central Finland. In the autumn of 1966 needle colour was determined by using Muncell Color Charts which allowed a quantitative measurement of three colour dimensions (hue, value, and chroma). Terminal shoot growth was recorded for two years after colour measurements. In both species, fertilization (NPK in the spring of the year of colour measurement) as well as other site factors caused differences in all three dimensions of needle colour. A regression of shoot growth on needle colour was found in both species. In most cases colour value (darkness) and, in spruce, also chroma, predicted the subsequent growth almost as well as did these two-colour variables together.</p>
<p>The PDF includes a summary in English. </p>