Ivan wrote [in part]:
Also, it looks as if though the mandarin tree has never been prunned --
Is there a guide I should follow when doing so?

Unlike stone or pome fruits, citrus is never pruned to promote fruiting.
Citrus is pruned to remove deadwood and branches that interfere with
each other. Some commercial growers also prune to keep the branch ends
from touching the ground (to reduce the access to the tree by ants and
snails). In a home garden, you might prune to improve the aesthetics of
the tree or to keep the tree low enough to pick fruit without a ladder.

For my dwarf citrus in containers, I prune to keep the top growth
proportional to the confined root system so that the foliage does not
place an impossible demand for moisture and nutrients on the roots.
This is a constant nipping and pinching throughout the growing season,
not the concerted pruning effort I will soon start for my peach tree.

Lack of pruning for your mandarin should not be a concern.

--

David E. Ross
http://www.rossde.com/

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