One of the great things about working with wood is the variety of patterns, textures and colours that can be found in the timber. No two pieces are ever the same and it is this uniqueness that adds greatly to the appeal of timber as a material to build with.
Quilted Big Leaf Maple (http://www.hearnehardwoods.com/featured_wood_products/quilted_maple_lumber/highly_quilted_maple_boards.html)
Hardship produces character. This holds true not just for humans, but also for trees. Hardships for a tree are often in the form of physical injury, drought, fire or diseases. These trials for a growing tree can sometimes produce the most beautiful patterns, colours and grains. Burls, which are bulbous deformities that occur when the tree is stressed by injury or disease, produce highly figured timber with amazing grain patterns. These are often used by wood turners to produce bowls and pens.
Burl on Tree (https://en.wikipedia.org/wiki/Burl)
Maple and some other trees are very occasionally afflicted with a condition that causes many new buds to grow and then die. This results in tiny knots forming as the tree grows. The exact cause is not well understood, but the timber produced is sought after by woodworkers for it's beautiful "birdseye" figure (kind of looks like a birds eye if you squint). This "defect" is hidden beneath the bark within the tree and is only revealed after the tree is cut down and the birdseye figure is revealed.
Birdseye Maple Pen Blank
Ugly, battered and diseased trees produce beautiful timber. Nature is full of surprises...