Soils, Vegetation, Wildlife Flashcards
USDA Hardiness Zones (based on)
Average annual minimum winter temperature, divided into 10-degree F zones.
Non-profit organization dedicated to research and education; promotes the professional practice of arboriculture and fosters a greater worldwide awareness of the benefits of trees.
International Society of Arboriculture (ISA)
ISA’s (4) factors used to evaluate economic value of trees
size, species, condition / health, location
The single most important factor in governing the hardiness of a plant is :
Min. Temperature
Naturally occurring grasslands are a typical indication that ___ is not sufficient to produce trees.
Rainfall
Clay particle size (typ)
.002 mm
not visible
Silt particle size (typ)
.002-.05m m
not visible
Sand particle size (typ)
2-.05mm
visible
Describes the soil changes from soil to semi-solid to plastic to liquid as water is added to dry soil
Atterberg Limits
Moisture content in the soil at the threshold between semi-solid and plastic
Plastic Limit
Moisture content in the soil at the threshold between plastic and liquid
The minimum moisture content at which soil will flow under its own weight.
Liquid Limit
Moisture content in the soil at the threshold between solid and semi-solid
Water content, expressed as a percentage of the weight of oven-dried soil, at which further loss in moisture will not cause a decrease in its volume
Shrinkage Limit
The ability of organisms or tissues to function only with the presence of free oxygen
Aerobic
Soil that is devoid of interstitial oxygen (most often occurs in wetlands)
Anaerobic
Soil particles transported by wind
Aeolian
A type of soil with characteristics resulting from prolonged saturation and anaerobic conditions. May be bluish in color
Contributes to formation of non-decomposing organic matter; may have a high or low pH
Hydric Soil
The point at which soil acts like a liquid (typically occurs under earthquake conditions)
Associated with fine to medium grained sands and silts found in loosely packed layers. Greater soil density lowers risk (e.g. clay % of 15 or more substantially decreases the risk)
Liquefaction
The ability of a soil to hold together under pressure from a downhill force
Shear Strength
A group of processes where earth or rock material is loosened or dissolved and removed from the surface. generally caused by rain, snow, ice, wind, and human activity - construction in particular)
Erosion
Soil texture type most susceptible to erosion
Silt
Soil amendment that increases pH
Lime Wood ash Oyster shells Calcium nitrate Industrial CO (burned lime)
Soil amendment that decreases pH
Iron sulphate Aluminum sulphate Calcium sulfate Sulfur (sulfuric acid) Pine needles (organic) Pine sawdust (organic) Acidic peat (organic)
Soil amendment that decreases pH
Iron sulfate Aluminum sulfate Sulfur (sulfuric acid) Pine needles (organic) Pine sawdust (organic) Acidic peat (organic)
Ideal pH range for max. absorption of nutrients
5.5-6.5
A measure of the load per unit area that a material can withstand before failure
The ability of soil to safely carry the pressure placed on the soil by any engineered structure, without undergoing shear failure (shear strength = the ability of a soil to hold together under pressure from a downhill force)
The capacity of soil to support a given load applied to the ground. The maximum average contact pressure between a structural and the soil surface on which it rests that the soil can support without failure. Expressed as force per unit surface area. ALSO: “the measure of a soil to decrease in volume under the pressure of a given weight.”
Bearing Capacity
Resistance to crushing or buckling force
Compressive strength
Soil consistency that is hard and little affected by moisture
Cemented
Soil consistency where when moist may be crushed under moderate pressure
Firm
Soil consistency where when moist crushes easily under gentle pressure and can be pressed together into a lump
Friable
Soil consistency where when dry it is moderately resistant to pressure
Hard
Soil consistency where non-coherent when dry
Loose
Soil consistency where when wet, will be readily deformed by moderate pressure; will form a wire when rolled between thumb and forefinger
Plastic
Soil consistency where when wet, adheres to other material and tends to pull apart rather than pull free from other material
Sticky
Soil consistency where when dry, breaks into powder or single grains under slight pressure
Soft
The method of mechanically increasing the density of soil by reducing the total pore space
Soil Compaction
Angle of repose of drained sand
33%
Angle of repose of boulders
45%
Angle of repose of loam
45%
Angle of repose of compacted clay
65%
US FWS Wetland classification: open ocean and its associated coastline; includes tidal zones; most productive and fragile ecosystem on earth
Marine
US FWS Wetland classification: tidal waters of coastal rivers and embankments, salty tidal marshes, mangrove swamps (saltwater and brackish water)
Tidal waters of coastal rivers and embayments; salty tidal marshes; mangrove swamps; tidal flats
Estuarine
US FWS Wetland classification: related to rivers and streams (often bordered by Riparian Buffers)
Lacustrine: lakes, reservoirs, large ponds
Riverine
US FWS Wetland classification:
Associated with lakes, reservoirs, large pools
Lacustrine
US FWS Wetland classification: marshes, wet meadows, fens, bogs, playas and swamps
Palustrine
Low marshy ground containing peat rich in mineral salts; alkaline rather than acidic.
receives nutrients from groundwater
Fen
An area having wet, spongy, acidic soil composed chiefly of sphagnum moss and peat in which characteristic shrubs, herbs, and sometimes trees, grow. Organic soil, unlike other wetlands that have mineral soil.
A type of wetland found in northern climates characterized by acidic soils, rich deposits of organic material (such as peat), and a diversity of vegetation types.
Water source: rainfall
Bog
Consolidates the creation of smaller wetlands; transfers the responsibility of creating wetlands to others; provides incentives for people to restore wetlands.
Wetland banking / compensatory mitigation
Wetland Remediation Techniques
solidification, soil vapor extraction, incineration, bioremediation, soil washing, solvent extraction, dechlorination, phytoremediation, air sparging, passive treatment wells
A natural community where dominant plants are grasses
Grassland
Term used to describe a field of permanent grass used for hay, but also applied to rich, waterside grazing areas not suitable for arable cultivation
Periodically inundated wetland that may or may not have water present
Meadows
Area of soft, wet, low-lying land characterized by grassy vegetation that is not woody; often forms a transition zone between water and land
A type of wetland characterized by herbaceous vegetation no taller than 6 ft.
Marsh
A shallow central basin of a plain where water gathers after a rain and is evaporated
Playa
Narrow zone of habitats, may or may not be vegetated, directly associated with streamsides or lake shores, or similar immediately adjacent habitat
Riparian wetland
Areas of brackish, shallow water usually found in coastal areas and in deltas; also inland marshes in arid areas where the water has a high salt level due to evaporation
Salt marsh
Plant communities and trees and inhabit tidal swamps, muddy silt, and sand banks at the mouths of rivers and other low-lying areas regularly inundated by the sea but protected from strong wave and current action. Only woody species that will grow where the land is periodically flooded with sea water.
Mangrove
The ability of a soil to return to its original shape after being subjected to a load condition.
Soil Elasticity
The ability of a soil to be deformed under pressure without breaking apart
Soil Plasticity
A condition typically caused by iron deficiency and is typically manifested by yellowed leaves with green veins. Overwatering and lack of aeration are typically the cause.
Iron deficiency may be because iron is missing from the soil or because the iron is “tied up” and unavailable to the plant’s roots (may be due to a soil pH that is too high or too low). A magnesium deficiency may also cause leaves to yellow while veins remain green
Chlorosis
Condition of abnormal growth in vascular plants in which the apical meristem (growing top), which is normally concentrated around a single point and produces approximately cylindrical tissues, instead becomes elongated perpendicularly in the direction of growth, thus producing flattened, ribbon-like crested, or elaborately contorted tissue.
May be attributed to frost, insect, or physical damage early in a stem’s development
Fasciation (or “cresting”)
(3) Defining Attributes of Wetlands
Hydrology
Soils
Vegetation
Sign of Nitrogen Excess
Root burn
Sign of Over Watering
Root rot
Soil pH ranges
>8.5 = strongly alkaline 8.0-8.5 = medium alkaline 7.0-8.0 = slightly alkaline 6.0 -7.0 = slightly acidic 5.5-6.0 = medium acidic <5.5 = strongly acidic
Loam composition
Generally consists of 40% sand, 40% silt, 20% clay
Benefits of gypsum
Improves aeration
Well Graded Soil
Soil that has a wide range of even distribution of particle sizes, in which the small soil particles fill the voids created by the larger grains.
2 Most Important Factors in Determining Vegetation Types (Undisturbed Sites)
Moisture and temperature
Layers of sedimentary rock or soil, or igneous rock that were formed at the Earth’s surface, with internally consistent characteristics that distinguish it from other layers.
Strata
Soil texture type: small grain size, moderate permeability; high erodibility
Silty Soils (over 40% silt)
Platy, blocky, prismatic, granular, columnar, structureless
Soil Structure Classifications
A layer under the surface where the soil pores contain a mixture of air and water
Vadose Zone
Soil amendment that improves structure; also reduces salt toxicity in heavily irrigated soils; provides sulfur and calcium; may improve permeability; does not significantly impact pH
Gypsum (calcium sulfate dihydrate)
Macronutrient in soil that is an essential part of plant cell wall structure, which provides for cellular-level retention and transport of elements and plant strength overall; Signs of deficiency: deformed tips of leaves and little root growth
Calcium (Ca)
Soil texture type: low permeability / impermeable; heavy weight; expansive (heaves / swells when wet; shrinks when dry); low water availability at low moisture content; colloidal content describes presence of this particle in a sample (suspension of finely divided particles); particles do not rapidly settle out of suspension and are not readily filtered; erodible to highly erodible
Clayey Soils (over 35% clay)
Macronutrient in soil responsible for healthy growth, strong roots, fruit and flower development, greater disease resistance; enhances photosynthesis, nitrogen fixation, flowering, fruiting, maturation.
Phosphorus (P)
Natural sources of phosphorus
rock phosphate, guano, bone meal
Describes the arrangement of the solid components of the soil, of the pore space located between them, and formation of aggregates; influences soil permeability and aeration (important for plant growth); dependant on parent material, formation conditions, presence of clay and organics, recent management history (adversely affected by compaction and when soils are worked when wet - over 15% moisture content)
Soil Structure
The layers in a typical soil profile which have distinctly different physical, chemical, and biological qualities.
Soil Horizons
A soil profile layer : partially weathered rock fragments
Soil Horizon “C”
A soil profile layer : organic matter in a recognizable form, including leaves and partially decomposed matter
Soil Horizon “O”
Soil pH 7-14; usually associated with areas of lower rainfall; micronutrients may be less available in soils with low pH - optimal nutrient availability for most plants is bw 6.5-7.5; plants that prefer this soil type: barberry, lavender, salvia
Alkaline Soils (features / causes)
Contributing factors to alkaline soil
Parent material (limestone, sepentine)
Climate (low rainfall)
Moist soil, poor drainage
Signs of __ deficiency in soil: tips and edges of oldest leaves begin to yellow (chlorosis) and die (appear burned on edges)
Signs of Potassium Deficiency
Macronutrient in soil that is essential for photosynthesis; also helps activate many plant enzymes needed for growth; deficiency: yellowing of leaves and purple leaf margins
Magnesium (Mg)
Macronutrient in soil that is essential for protein production; helps in chlorophyll formation; improves root growth and seed production; helps with vigorous plant growth and resistance to cold; Deficiency: yellow and brown leaves
Sulfur (S)
Presence of significant amounts of water in the soil lowers its bearing capacity, particularly for clays and silts. Water is a lubricant, lowering frictional forces between individual soil particles (why many building foundations have sub-drains and constructed slopes along highways have extensive underdrain systems); engineering design looks at worst case scenarios.
Soil Water / Impact on Bearing Capacity
Soil texture type: drains quickly, light weight, non-expansive, erodible
Sandy Soils (over 45% sand)
When water carries nutrients out of the soil as it drains; occurs in sandy soils
Leaching
A test used to determine the amount of macro and micro nutrients in the soil, organic matter content, pH value, USDA soil classification; may be used to guide plant growth (right plant right place / amendments needed)
Soil Test Report
Signs of __ deficiency in soil: stunted, thin-stemmed, spindly; foliage (particularly lower leaves) may be red or purple
Signs of Phosphorus Deficiency
A soil profile layer: bedrock
Soil Horizon “D”
Micronutrients in Soil (types and their function)
Iron, manganese, zinc, copper, boron, molybdenum Availability in soil determined by: abundance of parent minerals present, chemical conditions in the soil (pH in particular), rate of nutrient movement in soil within compounds (many are immobile, which helps with retention) Signs of iron deficiency: chlorosis, death of leaf edges, stunted growth
A feature of soils that affects how well nutrients and water are retained; clays and organic soils hold nutrients and water better than sandy soils
Soil Texture
A soil profile layer : nutrients left by rain water leaching; hardpans & clay pans develop here
Soil Horizon “B”
Signs of Nitrogen Deficiency
Pale yellow green color (chlorosis), stunted appearance, thin stems. Impacts lower leaves more.
Soil texture type: Blend of soil types; highly valuable as agricultural soil; very good drainage, moderately permeable, high water holding capability; slight erosion potential; highly fertile; easily worked
Loam (typ. <40% clay w/ good particle size distribution)
Macronutrient in soil responsible for vegetative growth above ground; sturdy growth and rapid maturity; dark green foliage; helps seed and fruit production; improves leaf growth;
Nitrogen (N)
Natural sources of Nitrogen
blood meal, alfalfa meal, feather meal, fish emulsion, manure.
Soil pH 0-7; higher % organic matter; often associated with areas of higher rainfall; contributing factors: rainfall and leaching*, parent material, organic matter decay, harvest of high-yielding crops; (*reduces calcium, magnesium, sodium, potassium) ( e.g. silica oxide); macronutrients may be less available in soils with low pH; optimal nutrient availability for most plants is bw 6.5-7.5; plants that prefer this soil type: blueberry, azalea, heather, cranberry
Acidic Soil (features / causes)
Macronutrient in soil that helps plants resist diseases, prevents excess water loss and increases water uptake by roots; helps plants to adapt to environmental stresses, including cold; known to activate 80 different plant enzymes
K (Potassium / Potash)
Natural Source of Potassium
Potassium sulfate
Granite dust
Wood ash
Kelp meal
A soil profile layer : heavy non-recognizable organic matter mixed with minerals
Soil Horizon “A”
An indicator of soil fertility; positively charged plant nutrients are attracted to negatively charged clay particles and organics, results in reduced leaching. A higher value CEC = greater soil fertility
Cation Exchange Capacity (CEC)
Universal Soil Loss Equation (USLE); Revised Universal Soil Loss Equation (RUSLE)
An equation used to predict long-term annual rates of erosion based on rainfall, soil type, crop system, and management practices (average soil loss in tons per acre per year) Factors considered: rainfall, soil erodibility, slopes, vegetative cover, management
Address Soil Compaction
Loosen soil, aerate
Address Poorly Draining Soils
Install drain lines, bore through hardpan
Six principles of healthy soil management
1) Enhance organic matter 2) Avoid excessive tillage 3) Manage pests and nutrients efficiently 4) Prevent soil compaction 5) Keep the ground covered with vegetation or mulch 6) Increase plant species diversity
Maximum angle of a stable slope determined by friction, cohesion, and particle shape. Typically between 25-45 degrees for soils, sands, and gravels. Clays lose cohesion when saturation and may be as low as 15 degrees. Good soil structure (aggregation into peds) may permit a higher angle.
Angle of Repose
Soil at or below the freezing point of water for two or more years. Construction is difficult but may be addressed by piles, a thick gravel pad, or ammonia heat pipes
Permafrost
Elements of Vegetation Inventory (6)
1) plant communities 2) species lists 3) edge profiles 4) rare and endangered species 5) fire history 6) physiognomic profiles
Factors Influencing Plant Distribution (8)
1) Duration of growing season 2) Point of succession 3) Ground temperature 4) Continuous wind 5) Soil moisture 6) Soil depth 7) Disturbance 8) Wildlife populations and browse patterns
Vegetation Types (9)
1) Forest 2) Woodland 3) Savanna 4) Scrub 5) Grassland 6) Tundra 7) Swamp (wetland) 8) Marsh (wetland) 9) Bog (wetland)
Plants that tolerate high-salt soils (plant classification by habitat preference)
Halophytic
Plants that tolerate dry soils (plant classification by habitat preference)
Xerophytic
Plants that prefer moderately moist soils (plant classification by habitat preference)
Mesophytic
Plants that prefer wet soils or float in the water (plant classification by habitat preference)
Hydrophytic
Elements of wildlife inventory (5)
1) Species 2) Population 3) Distribution 4) Habitat values 5) Rare and endangered species
When a large plot is used to characterize the most representative plant community.
Releve
In general, a series of squares of a set size are placed in a habitat of interest and the species within those areas are identified and recorded.
Quadrant sampling
Soils on slopes tend to have:
Less developed soil horizons
Causes of chlorosis
Poor drainage Damaged roots Compacted roots High alkalinity Nutrient deficiency (N, K, iron, magnesium)
Classification system that distinguishes soils based on their engineering performance as a construction material.
Considers texture, gradation, plasticity, and organic matter content.
Broadly categorizes soils as:
Coarse grained (sands, gravels)
Fine-grained (silts, clays)
Organic (peat
Unified Soil Classification System (USCS)
