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Hortsense

Glossary


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All Glossary

TermDefinition
adelgidsa family of aphid-like insects that feed exclusively on conifers and typically are covered with white waxy material.
aesthetichas to do with appearance; beauty.
alkalinehaving a basic reaction, that is containing the OH- radical and turning red litmus blue when in solution.
alternatean arrangement of leaves or other parts not opposite or whorled; parts situated one at a node, as leaves on a stem; like parts succeeding each other singly with a common structure.
alternate hostone of two kinds of plants on which a parasitic insect or fungus (e.g., rust) must develop to complete its life cycle.
annualmaturing and living one season only.
antherspollen-bearing part of a stamen, borne at the top of a filament, or sessile.
anthracnosea leaf-, stem-, or fruit-spot type of disease caused by fungi that produce their asexual spores in an acervulus.
appendagessubordinate or derivative body parts.
armywormscaterpillar species closely related to cutworms. They often move in mass through crop stands while stripping plants of their foliage.
auriclesan ear-shaped lobe, generally used to describe the base of leaves or petals.
axilsthe main stem or central support of a plant.
bacteriaa unicellular microscopic organism that lacks chlorophyll and multiples by fission.
bacteriala unicellular microscopic organism that lacks chlorophyll and multiples by fission.
bacteriuma unicellular microscopic organism that lacks chlorophyll and multiples by fission.
basalpertaining to the extremity of an organ by which it is attached to its support; said of leaves when at base of plant only. See rosette.
biennialof two season's duration, normally flowering, fruiting and dying the second growing season from time of seed germination.
blighta disease characterized by general and rapid killing of leaves, flowers, and stems.
bractsa much-reduced leaf, often scale-like and usually associated with a flower or inflorescence.
callusa mass of thin-walled cells, usually developed as the result of wounding or infection.
caltropan herb with spiny pods; I.e., puncturevine
calyxthe outer set of perianth segments or floral envelope of a flower, usually green in color and smaller than the inner set.
cambiumA one- or two-celled layer between the phloem and xylem that produces both these tissues and results in diameter growth.
canesa long woody pliable stem rising from the ground.
cankera necrotic, often sunken lesion on a stem, branch, or twig of a plant.
cast skinsthe outer layer of an exoskeleton shed by an insect or mite and seen on leaves or twigs.
castingsfecal material; caterpillar pellets.
caterpillarin general, the larvae of Lepidoptera; in Hymenoptera, the larva of the saw-flies.
chlorosisof plants, fading of the color of the chlorophyll of plant leaves, caused by environmental stress, chemical deficiency, disease, insects, or mites.
chloroticof plants, fading of the color of the chlorophyll of plant leaves, caused by environmental stress, chemical deficiency, disease, insects, or mites.
cocoona covering, composed partly or wholly of silk or other viscid fiber, spun or constructed by many larvae as a protection to the pupa.
crawlersthe first stage (nymph) out of the egg of certain plant lice (scales, adelgids, etc.). This stage is quite mobile, while subsequent nymphal stages are stationary.
cultivarsan organism of a kind (as a variety, strain, or race) that has originated and persisted under cultivation.
cultivatedmaintained by humans.
cutwormscaterpillar stage of the night flying “millers” or noctuid moths.
deciduousrefers to trees or shrubs that shed leaves completely at the end of the annual growth period.
defoliationthe loss of needles or leaves due to pest activity, disease, or negative environmental response.
delayed dormanttime of year when dormancy is about to end; characterized by the beginning of bud swell.
desiccationthe drying or loss of moisture from a leaf or plant part.
diebackprogressive death of shoots, branches, and roots generally starting at the tip.
dioecioushaving unisexual flowers, each sex confined to a separate plant, said of species.
distortedtaking on a shape that is unnatural.
distortiontaking on a shape that is unnatural.
droughtperiods or conditions that demonstrate the lack of moisture or rain.
ELISAa test in which an antibody carries an enzyme that releases a colored compound, signifying the presence of the pathogen.
endophytean organism that grows within a plant.
eradicateto do away with completely.
eriophyida family of tiny plant feeding mites that possess only 4 legs; they are highly host specific (feeding on only one species) and their damage is predictable and often dramatic.
evergreenhaving green foliage throughout the year.
excrementthe waste products eliminated by an insect, principally from digestion; feces.
excretathe waste products eliminated by an insect, principally from digestion; feces.
fasciationa symptom characterized by fusing (and flattening) of such plant organs as stems.
fertile (stems)capable of producing fruit and seed.
flagthe loss of rigidity and drooping of leaves and tender shoots preceding the wilting of a plant.
flaggingthe loss of rigidity and drooping of leaves and tender shoots preceding the wilting of a plant.
flockedcovered with white cottony material so as appear like snow.
frasssolid larval insect excrement.
fruiting bodiescomplex fungal structures containing spores.
fungalreferring to a group of saprophytic and/or parasitic organisms that lack chlorophyll and conductive tissues, and often produce spores. Includes molds, rusts, mushrooms, smuts, mildews, and yeasts.
fungisaprophytic and/or parasitic organisms that lack chlorophyll and conductive tissues, and often produce spores. Includes molds, rusts, mushrooms, smuts, mildews, and yeasts.
fungusa saprophytic and/or parasitic organism that lacks chlorophyll and conductive tissues, and often produces spores. Includes molds, rusts, mushrooms, smuts, mildews, and yeasts.
gallsan overgrowth of plant tissue.
girdledshowing mechanical damage (often from pests) to tree or shrub trunks or limbs that results in inability of cambial tissue to transport nutrients to roots.
girdlingmechanical damage (often from pests) to tree or shrub trunks or limbs that results in inability of cambial tissue to transport nutrients to roots.
glanda general term applied to oil-secreting organs, or sometimes an obtuse projection or a ring a base of a structure.
gnarledknotty and twisted.
growth regulatora natural substance that regulates or interferes with growth functions in plants and insects.
grubsan insect larva; a term loosely applied, but more specifically to larvae of Coleoptera (beetles) and Hymenoptera (wasps, etc.).
herbaceoushaving no persistent woody stem above ground.
honeydewa sweetish excretion produced by certain insects notably aphids and scales; also an exudate from the surface of some galls.
hornwormthe immature stage or caterpillar of the hummingbird or sphinx moth family; characterized by having a rhino-like horn on the tail end.
immaturesusually the larval or nymphal stages of various insect groups.
infectionthe establishment of a parasite within a host.
larvaa young insect which quits the egg in an early stage of morphological development and differs fundamentally in form from the adult; in a strict zoological sense, the immature form of animals which undergo complete metamorphosis.
larvaea young insect which quits the egg in an early stage of morphological development and differs fundamentally in form from the adult; in a strict zoological sense, the immature form of animals which undergo complete metamorphosis.
larvala young insect which quits the egg in an early stage of morphological development and differs fundamentally in form from the adult; in a strict zoological sense, the immature form of animals which undergo complete metamorphosis.
leafleta foliar element of a compound leaf.
leafminerrefers to the feeding style of certain flies, caterpillars that feed between the upper and lower surfaces of leaves resulting in blotching or snake-like passages.
ligule(1) a strap-shaped organ; (2) (in grasses) a minute projection from the top of the leaf sheath; (3) the strap-shaped corolla in the ray flowers of Composites.
lobesa projecting part or segment of an organ as in a lobed ovary or stigma; usually a division of a lf., calyx, or petals cut to about the middle (I.e. midway between margin and midrib.
loopera geometrid or other caterpillar in which some or all the middle abdominal legs are wanting and which moves by bringing tail to thorax and forming a loop of the intervening segments.
maggotthe legless larva of Diptera.
membranousparchment-like texture
midgename for certain fly families.
midrib/midveinthe primary-rib or mid-vein of a leaf or leaflet.
mildewa fungal disease of plants in which the mycelium and spores of the fungus are seen as a powdery or downy growth on the host surface.
mutationsomething qualitatively new appearing abruptly without transitional forms or slow development; a sport; a potential species.
myceliaseveral hyphae, perhaps a considerable mass of hyphae, that make up the vegetative body of a fungus.
myceliuma hypha or mass of hyphae that make up the vegetative body of a fungus.
nativeinherent and original to an area.
necrosisin a dead and decayed condition; of or pertaining to necrosis.
necroticin a dead and decayed condition; of or pertaining to necrosis.
needle minersee leafminer (needle miners are only seen on conifers).
nematodesgenerally, microscopic, wormlike animals that live saprophytically in water or soil, or as parasites of plants and animals.
nocturnalof the night; applied to insects that fly or are active at night.
nodesa joint on a stem, represented by point of origin of a leaf or bud; sometimes represented by a swollen or constructed ring, or by a distinct leaf scar.
nymphsyoung insects which quit the egg in a relatively advanced stage of morphological development, differing from the adult in having the wings and the genitalia present only in an incompletely developed conditions; a young stage of insects with an incomplete metamorphosis, (e.g., stinkbugs, aphids, etc.).
oedemaa blister formation due to an increase in intercellular water in leaves.
oppositetwo at a node, as leaves.
overwinterssurvives the winter in a protected place in a state of physiological “shut-down”.
oxalate/oxalic acida very strong acid. (COOH)2
palmatedigitate, radiating, fan-like from a common point, as leaflets of a palmately compound lf. or veins or palmately-veined lf.
paniclean indeterminate infl. whose primary axis bears branches of pedicelled fls. (at least basally so); a branching raceme.
parasitesany organisms that live in or on, or at the expense of another; organisms living in such a way as to derive all nourishment from the tissues of the host.
parasiticreferring to any organism that lives in or on, or at the expense of another; referring to an organism living in such a way as to derive all nourishment from the tissues of the host.
perennialhaving a life cycle of three or more years.
petiolea stem or stalk; the slender segment between the thorax and abdomen in certain Diptera and many Hymenoptera; in the latter, a pedicel formed of only one segment, or the first segment of a two-segmented pedicel in ants; in plants, the slender stalk of a leaf.
pheromonechemical emitted to air currents by an insect to stimulate behavior of other members of species (e.g., mating pheromone).
photosensitiveresponsive (sensitive) to light.
physiologicalresulting from some unfavorable physical or environmental factor (e.g., light, temperature, water, soil nutrients, chemical, physical, or mechanical injury).
predaciousany animal that eats others; living by preying upon other organisms, as certain insects.
predatorsany animal that eats others; living by preying upon other organisms, as certain insects.
predatoryany animal that eats others; living by preying upon other organisms, as certain insects.
prostratelying flat on the ground; a general term.
pupathe resting inactive instar in all holometabolous insects; the intermediate stage between the larva and the adult; applied to all insect orders with complete metamorphosis.
pupaethe resting inactive instar in all holometabolous insects; the intermediate stage between the larva and the adult; applied to all insect orders with complete metamorphosis.
pupatethe resting inactive instar in all holometabolous insects; the intermediate stage between the larva and the adult; applied to all insect orders with complete metamorphosis.
regenerateto reform; to regrow.
rhizomesan underground stem distinguishable from a root by presence of nodes, buds or scale-like leaves.
rhizomorphsa compact bundle of hyphae that has an outer covering and serves as a survival structure.
rosettea crown of leaves radiating from a stem and at or close to the surface of the ground.
rosettingshort, bunchy habit of plant growth.
row coversfine netting placed over plants to prevent insects from getting at them (e.g. Agrinet, Remay, etc.).
russetbrownish roughened areas on skin of fruit as a result of cork formation.
russettingbrownish roughened areas on skin of fruit as a result of cork formation.
rusta disease giving a “rusty” appearance to a plant and caused by one of the rust fungi.
sanitationthe removal and burning of infected plant parts, decontamination of tools, equipment, hands, etc.
saturatedfull to capacity; in soil – very wet.
sawflynot a fly – a primitive wasp.
scaba roughened, crustlike diseased area on the surface of a plant organ or the common name of a disease in which such areas form.
scorch“burning” of leaf margins as a result of infection or unfavorable environmental conditions.
sepalsone of the units comprising the calyx; a usually green foliaceous element subtending the corolla.
serrations"tooth-like" edge at leaf margin.
sheathsany elongated, more or less tubular structure enveloping an organ or part.
shepherds crookappears like the handle or bent end of a walking cane.
shotholea symptom in which small diseased fragments of leaves fall off and leave small holes in their place or small holes in wood resulting from beetle boring.
silicasilicon dioxide (SiO2)
skeletonizefeeding by certain insects which leads to the elimination of all or most of the leaf tissue – often leaving only the veins.
smuta disease caused by the smut fungi, characterized by masses of dark, powdery spores.
sooty molda sooty coating on foliage and fruit formed by the dark hyphae of fungi that live in the honeydew secreted by insects such as aphids, mealybugs, scales, and whiteflies.
spikelets(1) a secondary spike; (2) one part of a compound inflorescence which of itself is spicate; (3) the floral unit, or ultimate cluster, of a grass inflorescence comprised of flowers and their subtending bracts.
spikes(1) a usually unbranched, elongated, simple, indeterminate inflorescence whose flowers are sessile; the flowers may be congregated or remote; (2) a seemingly simple inflorescence whose "flowers" may actually be composite heads (Liatris).
sporadicirregular events such as insect population outbreaks that are largely unpredictable.
sporescomprised of a single gametophytic cell, it functions as the reproductive unit of fungi and some primitive plants.
stamensthe unit of the androecium and typically comprised of anther and filament, sometimes reduced to only an anther; the pollen-bearing organ of a seed plant.
sterilebarren, not able to produce seed.
stipplingthe appearance of tiny white or yellow green spots on leaves resulting from mite, leafhopper, etc. feeding.
stipulesa basal appendage of a petiole, usually one at each side, often ear-like and sometimes caducous (falls of easily).
stolonsa horizontal stem that roots at its tip and there gives rise to a new plant.
succulentbearing a thickened, juicy, soft, fleshy appearance (e.g., new leaves, or thick-leaved plants like cactus).
symptomsthe external and internal reactions or alterations of a plant as a result of a disease, insect, or mite.
systemicspreading internally throughout the plant.
taprootprimary root that grows downward.
terminalssituated at the tip or extremity; opposed to basal.
toxicpoisonous
viabilitycapability of living.
viablealive; capable of living.
viralreferring to submicroscopic obligate parasites consisting of infectious nucleic acid usually surrounded by a protein coat.
virusa submicroscopic obligate parasite consisting of infectious nucleic acid usually surrounded by a protein coat.
virusessubmicroscopic obligate parasites consisting of infectious nucleic acid usually surrounded by a protein coat.
whorlarrangement of three or more structures arising from a single node.
wiltloss of rigidity and drooping of plant parts generally caused by insufficient water in the plant.
wings(1) the lateral petal of a papilionaceous flower; (2) a dry, thin, membranous appendage.
witches’ broomsbroom-like growth or massed proliferation caused by the dense clustering of branches of woody plants.
xylemwater-conducting element of a plant.