The legend of the dogwood tree:
It is said at the time of the Crucifixion, the dogwood was comparable in size to the oak tree and other monarchs of the forest. Because of its firmness and strength it was selected as the timber for the Cross, but to be put to such a cruel use greatly distressed the tree. Sensing this, the crucified Jesus in His gentle pity for the sorrow and suffering of all said to it: "Because of your sorrow and pity for My sufferings, never again will the dogwood tree grow large enough to be used as a gibbet. Henceforth it will be slender, bent and twisted and its blossoms will be in the form of a cross -- two long and two short petals. In the center of the outer edge of each petal there will be nail prints -- brown with rust and stained with red -- and in the center of the flower will be a crown of thorns, and all who see this will remember."
Of course this is legend, but beautiful symbolism of the Cross. The Truth we know is that...
"The cross was two pieces of dead wood; and a helpless, unresisting Man was nailed to it; yet it was mightier than the world, and triumphed, and will ever triumph over it." - Augustus William Hare