• Gray, James R.
  University of Maine Graduate School
  

An investigation was conducted to examine the suitability of ten color reactions for studying lignification in balsam fir, Abies balsamea (L.) Mill. Two experiments were carried out on material collected on two different dates. In each experiment slides of fresh, FAA-killed, and FAA-killed celloidin-embedded material of normal and compression wood were stained and evaluated.

This study emphasized the need for considering each of the ten color reactions on an individual basis, since each has particular advantages and disadvantages. The best general stains for observing lignification were 2-thiobarbituric acid and the phloroglucinol reaction. Because of the color contrast between lignin and cellulose, the best stain combination for photomicrographic work was safranin-celestine blue; the poorest stain was benzidine.