I have planted a contorted white pine in a garden rockery as the main accent. However, I don’t want this tree to reach its full height of roughly 25′. Can I aggressively prune this specimen to keep it within 10 to 15 feet high and compact? If so, what advice would you have for trimming and when to do this
You have chosen a beautiful and unusual tree as an accent piece. According to various tree nurseries (such as https://www.connonnurseries.com/index.cfm/fuseaction/plants.plantDetail/plant_id/3018/index.htm) the tree will grow to 12 feet in 10 years, but eventually reach up to 40 feet.
To keep the shape and size you want, follow the recommended pruning of removing new growth only, but be sure to do this every year. Such pruning will ensure compact growth and maintenance of a lovely shape.