Silvics: Think about how trees are designed and pressured by Shade Tolerance, Regeneration method (seed v vegetative), Disturbance history, and Longevity & growth rate.

Silvicultural system: Treatment or prescriptions that are aimed to achieve specific stand objectives.

For example, someone is managing a sugar bush (they will need to look at selection).
Someone managing timber for ship masts, flooring, furnishings... might need White Pine or Oak belong to the shelterwood prescription.
And someone managing timber for construction for wafer board, tools, pulpwood etc.. supply, might need a clearcut prescription for Aspen, Black Spruce... etc.

To elaborate on this
Lets focus on Sugar Maple which is a shade tolerant species, long lived, regenerates happily under a close canopy. Selection is a good match because it focuses on small gaps, individual or group removal and continuous forest cover. With time, filtered light (seedlings dont like full exposure), and stability the systems maintains and uneven aged stand structure.

Now lets pivot to Eastern White Pine (or Oaks) which needs partial light to establish and full light to mature in the shelterwood system. This focuses on gradual canopy removal, seed trees left standing, protection from harsh exposure which imitates surface fires, windthrow and canopy thinning. This prescription is a polite, controlled substitute for fire.

In addition, there are species like Aspen which regenerate primarily through suckering instead of seed. Clearcuts stimulate a hormonal response in roots and the result produces dense, even-aged stands relaying full sun as the after effect of a wildfire or major disturbance.
In relation to clearcutting methodology, Black Spruce is also tightly linked to fire cycles and can regenerate naturally (or with planting operations).

www.ontario.ca citation

In Ontario forest management, a silvicultural system is a planned sequence of treatments applied to a stand over time to:
Regenerate the forest
Tend and grow desired species
Maintain forest health and productivity
Meet ecological, economic, and social objectives

Variabilities include:
Forest region (GLSL vs Boreal)
Natural disturbance patterns
Species ecology
Site conditions
Desired future forest condition
Ontario’s approach is strongly grounded in emulating natural disturbance regimes.

The FGS recognizes three primary silvicultural systems that differ in harvest pattern, regeneration method and stand structure over time.

Clearcut
The clearcut system removes most or all trees in a stand in one operation or a series of closely timed operations. Primarily in the Boreal Forest and some GLSL forest types because they are naturally shaped by large-scale disturbances such as wildfire.
Many boreal species regenerate best after stand-replacing events.
Jack Pine
Black Spruce
Trembling Aspen

Regeneration
Typically natural where overstory trees are removed once regeneration is established for a more natural forest preserves genetic diversity. The stand structure outcome is generally even-aged or two-aged stands with a transition from mature stand to new cohort.
Natural regeneration (seed, suckering)
Artificial regeneration (planting, seeding)
Often combined with site preparation
Stand structure outcome
Even-aged stands
Uniform cohort establishment

Shelterwood
The shelterwood system removes trees in a series of planned cuts, leaving some overstory trees temporarily to provide seed and shelter for regeneration.
Common in the Great Lakes–St. Lawrence Forest, particularly for:
White pine
Red pine
Oak
Yellow birch

Selection System
Primarily in tolerant hardwood and mixedwood stands in the GLSL Forest. Used to mimic small-scale gap disturbances. Suited to shade-tolerant species such as:
Sugar maple
Beech
Hemlock
Yellow birch (group selection)

Mixed Forest