Now that I have discussed tomentosa's nature and pruning methods, you must understand plantation management before you can prune.
I classify three distinct phases of plantation management. The first phase is establishment and root development. The second phase is height development. The third phase is diameter development. Tomentosa's growth should be fast and rapid during the first two phases. The third phase is when you are actually growing your board feet for future sales. Your market should determine the growth rate of this third phase. The management of the second and third phases can be based largely upon pruning. Successful growth management is based upon proper pruning of the lateral buds and limbs. You must also match pruning to the site's ability to produce growth. Don't try to grow a 30 foot log when your site can only support a few feet of growth a year. You want to grow a 30 foot log when your sit will produce a 20 foot sprout the coppiced year.
As mentioned, the second phase is height development. Depending on your goals and site, this phase may take from one to 10 years. After the coppice year, you must develop log length through yearly log extensions. You must force height growth through proper pruning techniques, stepping the log up higher each year until your desired height is reached. In the process, you must always maintain proper stem stiffness. You must have adequate diameter growth to support the crown's weight. If you don't, the tree is going to be top heavy and have poor form. The tree will bend over.
Let me talk about the crown to clear trunk relationship. It is a very important concept in tomentosa management. Let's take two trees both of which are 40 feet tall. Tree A has a clear trunk of 10 feet, the remaining 30 feet is crown height. Tree B has a 30 foot clear trunk, the remaining 10 feet is crown height. Which tree's trunk will have the fastest diameter growth? The answer is tree A. Not only does tree A have three times the foliage to produce wood fiber on the trunk, it only has to put it on 1/3 the length. This is a nine fold difference! When all growth factors are non-limiting, you will see a tremendous diameter growth rate when the ratio is greater than 1/1. This rule (Crown to Clear Trunk Ratio) is important to follow when you have gotten your plantation's height develop and are starting to concentrate on diameter growth.
As mentioned earlier, the third phase is diameter development and board foot production. This is the time to maintain your desired diameter growth rate. Height is no longer a concern. This is the time to keep accurate diameter measurements every two to four years. You need accurate records to make sound management decisions. If diameter growth is too rapid, you may need to reduce crown size by de-limbing. If diameter growth is too slow, you may need to do a partial harvest to release competition. You need accurate records to know your lumber volumes and lumber quality. These records will document the true value of your plantation whenever that information is needed. Record taking does not required a lot of equipment. You need a measuring device such as a tree caliper or a measuring tape. You need a permanent label so that you can identify each tree, and a pencil and paper. Record keeping is very important for good management. Without it, you won't know how to properly manage the third phase.
A main concern in the third phase is maintaining your predetermined crown/clear trunk ratio. This ratio is based upon the markets you are catering to. A ratio of .25 would be geared for slow diameter growth. It would be managed for the high price Japanese markets. A ratio of 4 would be geared for rapid growth. It would be managed for other specialty markets here in the USA.
You must also have a balanced crown. Not only do the Japanese grade on annual ring tightness, they also grade on the pith being centered. You must have a balanced crown to have a log with a centered pith. A balanced crown is one that has the same amount of foliage on all sides of the tree. For example, if the crown has no foliage on the north side and full foliage on the south, east, and west, the pith will be off center, favoring the north. You need a balanced, uniform crown on all sides so that equal amounts of wood fiber will be produced and laid on all sides of the trunk.