Christmas tree cultivation tractors, and shaper sheers. Mechanized planters, at a cost of about US$4,000, are not essential but a work-saving luxury for farmers. Farmers can purchase seedlings, the lifeblood of a Christmas tree farm, from nurseries. One farmer in Oregon purchased seedlings for between US$200–300 per 1,000 plants. The farmer, a wholesaler, sold his final products for about $20 each; after the cost of the trees and other expenses, a profit of $2–3 per tree. The best-selling species in the North American market are Scots pine, Douglas-fir, noble fir, balsam fir, Fraser fir, Virginia pine, and eastern white pine, although other types
Tree automaton three statements are equivalent: Tree automaton A tree automaton is a type of state machine. Tree automata deal with tree structures, rather than the strings of more conventional state machines. The following article deals with branching tree automata, which correspond to regular languages of trees. As with classical automata, finite tree automata (FTA) can be either a deterministic automaton or not. According to how the automaton processes the input tree, finite tree automata can be of two types: (a) bottom up, (b) top down. This is an important issue, as although non-deterministic (ND) top-down and ND bottom-up tree automata are