Glossary

safe working loadsee working-load limit.

safetyproactive process of preventing injury. damage. or loss.

safety climatea snapshot in time of a company's focus on safety. often situational. may be temporary. and oftentimes influenced by management. Generally strong immediately following an incident (contrast with safety culture).

safety culturea shared group of values or accepted social norms among workers regarding worker safety. often difficult to change (contrast with safety climate).

safety eyeglassesprotective eyewear that must be worn when conducting tree care operations.

safety factorstructural capacity of a system beyond the expected normal or actual loads. how much stronger the system is than it usually needs to be for an intended load. For example. a system with safe working load of5.000 lbs. and a safety factor of 2.0 would have a rated load of 10.000 lbs. (compare to(...)

safety lanyarda short rope equipped with snaps used for temporarily securing a climber in one place (see lanyard. work-positioning lanyard. flip line. and buckstrap).

salinewater solution containing dissolved salt.

saline-sodic soilSoil that contains sufficient sodium to interfere with the growth of most crop and landscape plants

saline-sodic soilssoils with high concentrations of both soluble salts (saline) and sodium ions (sodic) (see saline soils and sadie soils).

saline soilssoils with a high concentration of soluble salts. Can cause poor plant growth.

salinitythe amount or percentage of salt in the soil.

salt indexosmotic potential ratio of a fertilizer compared to sodium nitrate. based on the relative value of 100. The higher the salt index. the more likely plant damage will occur.

samaradry. winged fruits that remain closed at maturity.

sandsoil particles with a size between 0.06 mm and 2.0 mm in diameter (contrast with clay and silt).

sanitationcultural practice of removing dead. infested. or diseased plant parts to reduce the spread of insects or disease.

sapterm used for plant fluids found in cells or transported through the vascular system.

sap leakagedripping of sap from a pruning cut. rubbing. or other wound (see bleeding).

saplinga young tree about 1 to 3 years old. typically larger than a seedling.

saprophyteorganism that lives on and may act to decay dead organic matter (contrast with epiphyte and parasite).

sapwoodouter wood (xylem) that contains living cells and is active in longitudinal transport of water and solutes (contrast with heartwood).

sapwood rotdecay located in the sapwood. Bark and/or cambium may be damaged or dead. Signs of this classification of rot are usually numerous. but small. fruiting bodies along the bark's surface are common.

SARsodium absorption ratio

saturated pasteMixture of soil and water commonly used for measurements and for obtaining soil extracts

saturation pointpoint at which a soil or an aquifer will no longer absorb any amount of water without losing an equal amount (compare to available water. field capacity. gravitational water. and permanent wilting point).

SBDsoil bulk density. sudden branch drop

SCASociety of Commercial Arboriculture

scabbardprotective sheath for a pruning saw or other tool.

scaffold1) pertaining to tree architecture or form. a strong and properly spaced arrangement. framework. or system of branches throughout the crown. 2) a work platform. which may be stationary or moving. scaffold branches permanent or structural branches that form the scaffold architecture or(...)

scaffold branchespermanent or structural branches that form the scaffold architecture or structure of a tree.

scaffold knotsee double fisherman's bend.

scaleone of a group of insects that attach themselves to plant parts. Most scale insects are parasites of plants. feeding on sap drawn directly from the plant's vascular system.

scarf cutwedge-shaped cut forming the front of the hinge used in tree or limb removal (see face notch).

scheduled tree maintenancemethodical. systematic approach to determining when and how often tree care activities will be performed. Contrast with by-request service.

Schwabischtype of friction hitch used in climbing and rigging.

scion1) top part of a graft. with leaves and buds. that is grafted to the stock or root stock. 2) woody tissue (that does not require buds) used to complete a bridge graft.

sclerophyllousHard-leaved; leaves resistant to drought by having a great deal of sclerenchymatous (hardened) tissue and reduced intercellular spaces

scorchbrowning and shriveling of foliage. especially at the leaf margin.

screw linkconnecting device with a threaded closure mechanism. Used to secure equipment or tree sections in rigging operations.

secateurshook and blade or scissors-type hand pruning tool intended for cutting single. small diameter stems. Also called pruning shears. bypass pruners. or hand pruners (contrast with anvil-type pruning tool and hand pruning shears).

secondary disorderdisorder that develops after a plant is stressed by a primary one.

secondary growthincrease in root and stem girth or diameter. Occurs at lateral or secondary meristems in some vascular plants such as dicots.

secondary injuryInjury or problem caused by a primary injury. problem. or infection

secondary nutrientNutrient required in moderate amounts by plants such as calcium (Ca) and magnesium (Mg).

secondary nutrientsmineral elements. such as calcium (Ca) and magnesium (Mg). required in moderate amounts by plants (see also essential elements. macronutrient. micronutrient. and primary; elements).

secondary pestinsect or other pest problem that develops on a plant stressed and weakened by another factor (see secondary disorder).

secondary pest outbreakincrease in a secondary pest population following a reduction in the population of natural predators or parasites.