salt burn - the brown or black leaf or leaf edges that appear when the plant is exposed to excessive amounts of a form of chemical salts such as granular fertilizers. Water moves from low concentrations of salts toward high concentrations. Therefore, when a clump of a salt compound comes into close proximity to plant tissue, it pulls all the water out causing the cells to collapse and the tissue to "burn" or turn brown.

A similar reaction occurs when fresh (uncomposted) manure come into contact with plant roots. When composted over time, the salts in the manure are leached out by rain water.

Dog urine has the same effect on turfgrass.

samara - an indehiscent, single-seeded, dry, winged fruit found on plants such as elms (Ulmus) or maples.
sand - mineral soils are composed of particles of sand, silt and clay. Sand is the largest of the particles at 0.05 to 1.0 millimeter in diameter. With such big particles, it provides large air and water pores and is extremely well drained. Sand particles have a low CEC which means that they do not hold on to nutrients well.
sanitation - often times, giving the garden a good cleanup in the fall is a fine way to prevent insect and disease problems. Many insects and disease over winter on or in the debris left over from the current year's growth.

If you have experienced a serious insect or disease problem, identify the organism and determine how it spends the winter. If it hides as an adult, lays eggs or develops spores on the abandoned leaves or stems, you may benefit from removing these from the garden after they have been killed by a frost in the fall.

In extreme cases, this may also include sterilizing the soil to kill organisms in the soil. This is a process that is most often done with harsh chemicals that can only be applied by licensed companies. They are too dangerous for use by the typical homeowner.

sapwood - this is the "new" wood found just inside the cambium layer on a dicotyledon type of tree. It is lighter colored than the heart wood which is closer to the center of the trunk. Sapwood is also still live cells that are involved in the movement of water up the tree and sap down the tree in the xylem and phloem cells.  
saturated - a term to describe the situation when all the pores in the soil are filled with water. This excludes the needed air spaces and, if it persists over a long time, may cause the death of roots and encourage root rot.
scaffold branches - these are branches that extend out laterally from the main trunk of a tree. This term is most often used for fruit trees where scaffold branches are chosen for their location and strength for supporting a crop of fruit.
scape - (aka flowerscape) usually refers to the entire stem that bears a complete set of flowers.

In hostas, it is the stem that has a complete set of flowers on a single division. The scape tends to arise directly from the crown of the plant in the ground.

scarification - some plant species produce very hard seed. In nature, this results in some of the seed staying in the ground for several seasons before germinating. This spreads out the risk that seeds will germinate and emerge during a bad year which could result in all of them dying.

Scarification is a process where the seed is artificially softened or the seed coat is opened slightly so that all the seeds will germinate at once. Seeds may be scarified by soaking them in hot water or a mild acid solution. They may also be notched with a fingernail file or sandpaper to break the seed coat and allow water to enter.

scientific name - (aka Latin or Greek name) the system of naming plants developed by Carol Linnaeus whereby every plant or animal type has a specific name consisting of two parts (binomial nomenclature), the genus and species. An example would be Hosta sieboldiana.
scion - grafting involves the combination of two plants into one. The upper part of the graft is called the scion.

In the case of hybrid tea roses, this would come from the plant that has the beautiful flowers but roots that are not winter hardy.

The lower part of the graft is called the rootstock or stock. In hybrid tea roses, this would be from some "wild type" of rose that is extremely winter hardy but does not produce beautiful flowers.

scorch - this is a symptom that shows a browning of the edges of leaves. It is most commonly the result of excessive heat or insufficient water from the root system.
secateurs - a French word used by British gardeners for hand pruners or pruning shears.
seed coat - the protective outer layer of a seed.
seedling - a plant grown from a seed and therefore, the result of sexual reproduction. It is not a clone.
seeds - the result of the combination of the pollen from a male reproductive organ (stamen) with the egg of the female reproductive organ (pistil). Plants grown from seeds may display phenotypic variations that will not be evident in plants reproduced asexually (divisions, cuttings, tissue culture, etc.).

The seeds of hostas are dark brown or black when they are ripe. They may be planted immediately after harvest or may be stored in a freezer for later sowing. 

seersuckering -  a leaf characteristic caused by the gathering of tissue between the veins giving the leaf a "bubbled" effect as if thread had been pulled out of a piece of material.
selective pesticide - a pesticide that will be toxic to some organisms but not to others. A common example is broadleaf herbicides which will kill dandelions and other broadleaf weeds but will not bother grasses.
selfing or selfed - (aka self-pollination)  refers to the movement of pollen from the stamen to fertilize the eggs in the pistil of the SAME plant. This may result in the expression of recessive traits of the parent plant.
self-fertile - describes a plant that can he pollinated by its own pollen or that of another plant of the same variety.
or self-unfruitful
- describes a plant that cannot he pollinated by its own pollen or that of another plant of the same variety.

Apple trees, for instance, must have at least two different cultivars in the vicinity to produce apples. A red delicious tree cannot pollinate itself or another red delicious tree.

self-pollination - describes a plant that has been pollinated by its own pollen. Generally, this refers to the situation where a hybridizer manually takes the pollen from the stamen and transfer it to the pistil of the same plant. Although it still mixes two sets of genetic materials, being from the same plant, it should result in offspring that do not vary much from the mother plant.
self-sterile - See self-infertile
semi-evergreen - a plant that is evergreen in its preferred climate zone but may lose some of its foliage in colder or warmer zones.
senescence - when something senesces, it is getting ready to die. Herbaceous plant parts above ground go into senescence late in the season.
sepals - a modified leaf at the outermost layer of the flower.

The sepals are collectively called the calyx and act as a protective covering for the inner flower parts when they are in the bud. Sepals are usually green, but in some species they are the same color as the petals. In this case, the combination of the sepals and petals is called tepals. Hostas have tepals in their flowers.

In some groups of plants sepals are absent or may consist of bracts.   

serrate - a leaf having sharp forward-pointed teeth on the margin.
sessile - plant parts like flowers, leaves or fruit which are attached directly to the plant without any stem, peduncle, pedicel or petiole.
sexual reproduction - in plants, it is the combination of the pollen from a male reproductive organ (stamen) with the egg of the female reproductive organ (pistil) resulting in the production of seeds. This results in the combination of the genetic material (genotype) from two plants (except in the case of self-pollination) which results in phenotypic variability in the seedlings.
shearing - refers to non-specific pruning of plant foliage with hedge shears. It cuts everything back to a specific height without regard to buds. Shearing should be limited to hedges, topiary, or where a formal garden is to be maintained.
shoot - usually refers to a single stem with leaves that emerges from a bud on the crown in the ground.
shot hole - certain fungal or bacterial leaf spot diseases will weaken the tissue on a leaf so much that the tissue drops off in the wind. This leaves a small opening in the leaf called a shot hole since they often resemble a leaf that has been shot with a shotgun.
short day (SD) - a plant requiring exposure to short days (often less than 12 hours) to initiate production of flower buds. In fact, it is often the amount of darkness that is important. Many of these plants need to be exposed to more than 12 hours of total darkness to trigger bud formation.

See Long-Day Plant, Short-Day Plant and Day Neutral Plant

shrub - although not a precise definition, it generally refers to woody plants that have several stems originating from the ground and no distinct single trunk. 

Images of Shrubs.

sign - when diagnosing a plant problem, we can look for signs and symptoms. A sign is an indication of the presence of the causative agent. For instance, holes in a leaf are signs of feeding by an insect. A mushroom is a sign that a fungus is at work.

See Symptom

signal word - warning words required on pesticide labels which give a relative indication of the product's toxicity. The signal words are either “Danger Poison” for highly toxic compounds, “Warning” for moderately toxic, or “Caution” for slightly toxic materials.
silt - mineral soils are composted of particles of sand, silt and clay. Silt are intermediate sized particles that are smaller than sand and larger than clay.
simple leaf - most plants have simple leaves which consist of a petiole (leaf stalk) and one leaf blade.
See compound leaf.
skeletonizing - a sign that describes the damage done to a leaf by insects. Beetles often feed on the tissue between the veins of the leaf. Eventually, all that is left of the leaf are the veins which make it appear like a skeleton.
slow release - used to describe a fertilizer that is not very water soluble and, therefore, releases its nutrients to the soil slowly. These fertilizers are often coated in clay, plastic-like compounds or other materials which must be broken down by weathering or by microorganisms before the nutrients inside are released to the soil.
slugs - these are mollusks which are best described as snails without shells. They crawl along on a slime trail to keep themselves moist and love an environment that is cool, moist and has decaying organic matter.  Slugs are the number one pest of hostas because they too prefer a cool, moist environment.

Slugs generally feed at night and chew holes in the leaf blade and may also feed on the petiole of hostas

More on Slugs...

small size - according to the The American Hosta Society, there are five size categories of hosta including Giant, Large, Medium, Small and Miniature.

Small hostas form a clump that is 6 to 10 inches in height.

soaker hose - generally a hose with very porous walls that will allow water to gently seep out over time. They save water use by applying water only near the root zone of plants and help prevent diseases by not getting the foliage wet.
soil - often the uppermost layer of the earth's surface which consists of disintegrated rock (parent material) and organic matter (humus and living organisms).

More on Soil...

soil heaving - the alternating expansion and contraction of soils (especially those with high clay content) caused by freezing and thawing conditions during the winter. In the process, plant roots may be damage and, in some cases, recently planted perennials may be pushed (heaved) out of the ground.
soil pore spaces - spaces or cavities in the soil not occupied by solid particles. These are the places for air and water in a healthy soil. There should be about 25% by volume of air space and 25% by volume of water space in the ideal soil for plant growth.
soil structure - the physical composition of soils which expresses itself in terms of soil horizons.

More on Soil Profile...

soil test - an analysis of a soil sample to determine the level of nutrients, soil type, pH and other chemical parameters.

More on Soil Tests.

softscape - all the living elements i.e. plants, fish, in a landscape.
See hardscape.
softwood cuttings propagation method in which the plant segments for rooting are collected during the current growing season from new growth that has not matured or hardened off significantly.

See Hardwood Cuttings.

soluble salts - salt is a class of chemical compounds that has the characteristic of attracting water into it. For the gardener, it is of concern because most fertilizers and fresh animal manures have high levels of soluble salts.

When a clump of salt or fresh manure comes into contact with roots or other plant tissue, it will quickly draw the moisture out of the plant and into the salt. This will cause the plant cells to collapse, the tissue to die and turn brown. This rapid dehydration is commonly called a "burn."

somatic - relating to the cells in the "body" of the plant rather than in the reproductive tissue. The variegation in many plant leaves exists only in the somatic tissue and is, therefore, not transferred to the next generation through seed.

These variegated plants can be reproduced by division or tissue culture and will maintain their variegated tissue. They generally may NOT be reproduced in the same form from seed.

sp. - (plural =  spp.)  when only the genus of a plant is known, the abbreviation, sp. is used if it refers to a single species. If the reference is to two or more species, the abbreviation, .spp is used.

For example, if you are referring to all the species of Hosta, you would use Hosta spp. The name of the genus is capitalized and italicized or underlined while the sp. or spp. is not.

sphagnum moss - a type of coarse textured, long fibered peat moss that is often used during plant propagation since it contains a chemical that appears to suppress the fungal disease, damping off.

It is also used to line wire baskets used for annuals and ferns.

spatulate -  a leaf or plant part shaped like a spatula i.e. rounded more or less like a spoon.
species - in the hierarchy of the binomial nomenclature system, plants are grouped because they share certain characteristics. The most closely related plants are in the species, a little broader grouping is the genus and the next wider group is the family. Generally, members of the same species will interbreed freely.

To qualify as a species, there must be evidence that the plant currently lives or once lived in the wild. Some hosta "species" have been discovered to have never existing outside of cultivation by humans. Therefore, what was once a species called Hosta fortunei has been changed to cultivar status as Hosta 'Fortunei'

Although it is a little confusing, a species name consists of the genus name and a specific epithet which may be a descriptive word or a latinized version of someone's name. For example in the species, Acer palmatum (Japanese maple), Acer is the genus and palmatum (palm like leaves) is the specific epithet.

specimen - a term indicating a special plant in the landscape. This may be due to size or another unique characteristic.

In Hosta, it is often used to refer to a Giant size plant greater than 28 inches in height.

speckled - a leaf, stem or seed pod that has small spotted irregular coloring.
spider mites - tiny, eight legged critters that suck the juices from many plants in the landscape. Since they have more than six legs, they are not insects and certain insecticides will not work on them.

Mites are related to spiders but, technically, are not spiders. They do, in large populations, spin webbing around plant parts. Populations of spider mites will often suddenly explode on a plant and may disappear with the next pounding rainfall. They are often found feeding on the bottom of leaves.

More on Spider Mites.

spider shaped flowers - a flower with narrow, widely spaced petals that open upward and resemble the spread out legs of a spider.
spike  - a narrow flower inflorescence that is usually longer than it is wide with small flowers borne along one main stem.
splashed or streaked - a form of variegation with many non-connected light and dark colored sections often in streaks running nearly parallel to the midrib of the leaf.

In hostas, this type of variegation is usually considered unstable since it will often revert to the solid colored form. There are a few cultivars that are very stable, however, such as H. 'Spilt Milk'. Streaked plants must be used as the mother parent in cross-breeding of hostas to produce variegated seedlings.

spore - reproductive body of fungi and other lower plants, containing one or more cells: a bacterial cell modified to survive an adverse environment; sporulate means to produce spores
sport - one way that new cultivars are originated is through a naturally occurring mutation or chimeral rearrangement that is genotypically (genetically) or phenotypically (physically) different from the original plant.

In hosta, a single bud on a clump may produce a single division with a different color or variegations pattern. This sport can be separated from the clump and, if it remains stable i.e. does not revert to the original form in future seasons, and has unique characteristics, it may be introduced as a new cultivar.

spot treatment - spraying for weeds in only parts of the lawn that are infested rather than treating the entire lawn is an example of spot treatment. Also, treating only areas of a plant infested with damaging insects rather than applying to the entire tree.
spur - very short lateral branch where flower buds develop and fruit eventually forms. Most common in some types of apples and crabapple trees.
stable - refers to a hosta (or other plant) that maintains its solid or variegated pattern over time. This is often an issue with streaked or splashed hosta variegation which tends to be unstable and prone to reversions. In this case, such plants may change or "stabilize" into a single colored plant or one that has either medial (center) or marginal variegation while the streaked appearance is lost. This may happen to the entire plant or just a single division may revert to another form but the remainder of the clump keeps its original form.
stamen - male part of a flower consisting of a filament or stem and a capsule like structure at the top called the anther which produces the pollen.

Hybridizers manually move the pollen from the male parent to the pistil of the female parent when cross-breeding Hosta, Hemerocallis (daylilies) and other plants.

The number of stamens per flower varies by plant species and hostas usually have six stamens per flower.

standard - 1) may apply to a typical example of a species or cultivar that other plants may be compared to for identification.

2) certain plants such as fruit trees, roses, geraniums and others may be grown on top of an elongated stem. Sometimes this is accomplished by grafting a plant on top of a long stemmed rootstock. Other standards may be created by treating the plant with gibberellins to cause the plant to develop an unnaturally tall main stem.

3) in Iris species, this is the name for the upright petals of the flower.

sterile - the inability of the eggs in the pistil or the pollen in the stamen to complete fertilization and form viable seeds.

Hybrid plants resulting from the cross-pollination of two different species may result in a sterile progeny. Sterile hostas will flower but will not set seed pods on the flowerscape like fertile plants.

sticker - ingredient added to spray or dust to improve its adherence to plant leaves and stems.
stigma - the female reproductive organ of a plant is called the pistil. It consists of a stigma, style and ovaries. The stigma is the sticky knob on the top of the stem (style) that leads down to the ovaries. It is the place where the pollen lands to begin the process of fertilization during sexual reproduction.
stipe - in ferns, this is the slender stalk that supports the frond.
stipule - a pair of lateral appendages that look like small leaves that emerge from the base of the leaf petiole in certain plants such as Japanese Flowering Quince (Chaenomeles).
stolon - a horizontal stem above the surface of the soil, that takes root at the nodes which touch the ground.

Strawberries send out stolons (runners) from the mother plant to produce new plants.

This term is often used incorrectly for plants that spread by a rhizome which is an underground stem. Quackgrass spreads by rhizomes. Some hostas send out rhizomes which are below the ground stem modifications.

stoleniferous - a plant that spreads by stolons. See stolon.
stoma - (plural = stomata) an opening on the bottom of leaves which regulates the exchange of gases between the plant and the atmosphere. They have small organs on each side of the opening called guard cells which are capable of opening and closing in response to certain stimuli. Water vapor moves through the stoma which helps regulate water flow through the plant and cools the plant through evaporation. Carbon dioxide intake and oxygen discharge happens primarily in the stomata too.
stomach poison - a pesticide that must be eaten by an insect or other animal in order to kill it.
stratification - some plant species produce seeds which must be exposed to one or more periods of cold, moist conditions before they can germinate. In nature, this happens most often in tree species which normally drop their seeds to the forest floor in the fall to germinate the following spring after spending the winter buried in cold, moist leaf mould. This is smart because, if the seeds germinated when they dropped to the ground on a warm autumn day, they would probably be killed by the cold of the winter.

Stratification usually involves storing the seeds in moist peat moss at temperatures of about 40°F (refrigerator) for 1 to six months. The length of time may vary from species to species and you should consult a resource to find the requirements of your particular plant.

Of course, you can also just plant the seeds outdoors in the fall and let nature take its course. However, you lose control over the seeds and they just might disappear to become food for a squirrel.

streaked see splashed
striped flowers - some Hosta species or cultivars have purple stripes on their flowers.
strobilus - this is the name for the flowers of conifer trees or shrubs. The male flowers are slender similar to the catkins on birch trees. The female flowers look like miniature cones. Since they generally have separate male and female flowers, conifers are either monoecious or dioecious.
style - the female reproductive organ of a plant is called the pistil. It consists of a stigma, style and ovaries. The stigma is the sticky knob on the top of the stem (style) that leads down to the ovaries at the bottom.
sub-opposite - Sub-opposite refers to a condition where the leaves and buds are not spaced sufficiently far apart to be considered alternate nor are they perfectly opposite. They are in between these two extremes. Examples would include Common Buckthorn (Rhamnus cathartica), Katsura Tree (Cercidiphyilum japonicum), White Fringe Tree (Chionanthus virginicus).
subshrub - this is one of those terms that is not very clearly defined. Generally when it is used, it indicates a woody shrub that is quite small or is one that is prostrate or hugs the ground. It might also indicate a plant that may be considered a "perennial" but is not strictly herbaceous.

Example: Perennial candytuft (Iberis sempervirens) is a low-growing plant commonly called a perennial in the garden but it does maintain its foliage year around in mild climates like an evergreen shrub.
subsoil - the layer of soil directly beneath the topsoil which is characterized by a lower proportion of organic matter and less fertility than the topsoil.  
substance - in gardening terms, this is used to describe the texture or thickness of the foliage of a plant. It may also pertain to the mass of the overall clump. Hostas with a thick or heavy substance tend to suffer less from slug damage.
subtropical - a zone of the earth which only rarely experiences freezing temperatures. Areas of Southern Florida would be considered sub-tropical.
See temperate and tropical
subulate - the shape of a leaf or bract when it tapers from the base to the apex.
sucker - an unwanted shoot, often vigorous, that sprouts from the roots of a plant. These are common on certain grafted trees such as apples or crabapples. If the top of the tree dies, do not expect a sucker to develop into a good quality replacement. See watersprout.
sucking insect - an insect that damages plants by puncturing the leaves or soft stems with its tube-like mouth and feeding on the sap. Aphids, leaf hoppers and scale are common sucking insects. Spider mites also suck the juices from plants but they have eight legs and are not an insect.
sun scald - an injury to a plant from exposure to excessive sunlight and heat.
surfactant - a substance added to a spray that increases its wetting and spreading properties (also called wetting agents or spreader-stickers).
symptom - when diagnosing a plant problem, we can look for signs and symptoms. A symptom is a response by the plant to the presence of an insect, disease or environmental problem. For instance, the symptom, wilting, is the plant's response to a lack of water which could be caused by drought or by the presence of a fungus which clogs up the xylem.

See Signs  More about Plant Disease Symptoms

systemic - refers to something that moves through the vascular system of a plant. This can be a disease such as one of the wilt diseases or can pertain to pesticides which are either injected into the plant or absorbed by the root system and spread throughout the plant internally.


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