Propolis season. Normally, it is dark brown in color, but it can be found in green, red, black, and white hues, depending on the sources of resin found in the particular hive area. Honey bees are opportunists, gathering what they need from available sources, and detailed analyses show that the chemical composition of propolis varies considerably from region to region, along with the vegetation. In northern temperate climates, for example, bees collect resins from trees, such as poplars and conifers (the biological role of resin in trees is to seal wounds and defend against bacteria, fungi and insects). "Typical" northern temperate
Glue-size Glue-size Glue-size is a painting technique in which pigment is bound (sized) to cloth (usually linen) with hide glue, and typically the unvarnished cloth was then fixed to the frame using the same glue. Glue-size is also known as distemper, though the term "distemper" is applied variously to different techniques. Glue-size was used because hide glue was a popular binding medium in the 15th century, particularly among artists of the Early Netherlandish period, who used it as an inexpensive alternative to oil. Although a large number of works using this medium were produced, few survive today, mainly because of the