[This is a work in progress. There is a bit of copying from other sources (Wikis, Forum) and formulas may not be updated. As a newer player, I found it hard to get up-to-date information on this all in one place and wanted to compile what I have found for people to help fact check and to help others.]
Stewardship of a forest requires attention to detail and a good amount of patience. The Forest Steward must be supported by a capable potter (to build the kiln that fires the Treeplanting Pots) and carpenter (to build the Herbalist Table to sprout the trees) but in turn supports these occupations with higher quality wood or they must do these things themselves.
The Process...
To plant a desired seed, one will put it inside of a Treeplanter's Pot with Soil x4 and Water 1.0L. All of which will be placed on an Herbalist Table for 5 in-game hours (approx 1.5 real hours). The Herbalist Table can hold up to four Treeplanter's Pots and I personally recommend two Herbalist Tables to either be able to grow a variety of saplings or to minimize the death of a desired crop.
Forest Stewards will want to continuously increase the quality of the forest which they are tending. In order to do so, the supporting industry must also improve.
The quality of a planted tree depends on these factors:
tree_q = (2*qSoil + 2*qWater + 3*qPot + 3*qTable + 15*qSeed) / 25 then +/- 5
The total quality is also softcapped by the seed planter's Farming Skill. In order to improve the quality of the pot and herbalist table, read onward.
The Kiln
Skills Required: Pottery
Objects Required: Clay x45
End Quality: avg(clay_q) (see Resource Quality)
The quality of items produced by the kiln is product_q = 1/2 unburntpot_q + 1/4 fuel_q + 1/4 kiln_q.
The quality of an unburnt treeplanter's pot is softcapped by the DEX (dexterity) of the crafter. It is easier to find higher quality branches early on in the process for fuel than high quality blocks.
The Herbalist Table
Skills Required: Plant Lore
Objects Required: Block of Wood x4, Board x4, Plant Fibers x8
End Quality: ( (fiber_q*2) + board_q + blockwood_q ) / 4
The quality of products produced on an Herbalist Table is the average of the precursor item (potted tree) and the table quality.
As the Forest Steward provides higher quality wood, the quality of the fuel used to fire the treeplanter's pots and the blocks of wood and boards will increase. The better pots and herbalist table will further increase the quality of new saplings planted.
Resource Quality
Board quality is softcapped by the Carpentry Skill but is otherwise determined by:
sqrt ( saw_q * lumber_q). To make higher quality boards, bone saws are recommended because it is easier to make a higher quality bone saw than metal saw. This sacrifices two boards (4 instead of 6) per log but is important in the construction of higher quality Herbalist Tables.
Block of Wood quality solely relies on the quality of the tree.
Plant Fiber quality is determined by the quality of the seed used at time of planted, softcapped by the planter's Farming Skill.
Water, Soil, and Clay quality is a complex subject best described by the Ring of Brodgar wiki article: Finding high quality water, clay, and soil
The Forest...
Now that the process to nurture and maintain high quality trees is outlined, the trees and bushes chosen will be primarily up to the individual steward and their ability to find the seeds required.
List of Bushes with pictures
List of Trees with pictures
There are different reasons to grow different trees. A skilled Forest Steward will maintain a variety of trees, improving the quality each generation, with an end-goal in mind. Popular choices for different products are:
Item Production: apple, mulberry
Bough Quality: elm, spruce (produce multiple boughs)
Block Quality: blackthorn bushes (bushes grow quickly)
Log Quality: chestnut, walnut (produce quantities of seeds, harvestable earlier in the growth stages)
The Steward...
Skills & Complementary Industry
Aside from Farming, the major skills that benefit forest growth also benefit Silkfarming.
Woodsmanship (Cost: 12,500 LP)
Forestry (Cost: 25,000 LP)
Druidic Rite (Cost: 150,000 LP)
Since the Forest Steward already requires high quality Herbalist Tables, time spent tending to a Forest can also be spent tending to the production of silk. Since the Forest Steward can concentrate on improving the quality of Mulberry trees they can also improve the quality of silk over time. In order to do this, the Forest Steward would require both a high level of Farming & Sewing in order to maximize silk production.
Equipment
(future growth of article)