- abnormal growths that form on
plant roots, shoots, and leaves. Galls often result from
infection by a fungus,
bacteria, etc. or
such as a certain types of
As part of certain insect's life cycle, when they lay
their eggs on the leaf or stem of certain plants, they
also inject a chemical that stimulates the growth of a
gall. Inside the gall, the egg hatches and the new
creature feeds inside for a while before emerging to fly
away. That is why, on certain gall such as many that
grow oak trees, by the end of the season you will find a
nice hole in them.
general use pesticide
pesticide which can be purchased and used by
the general public without any special training or
- referring to
characteristics or groups of chromosomes inherited
through the process of sexual reproduction i.e.
seeds in plants.
- the genetic makeup of a plant which is inherited
through the process of sexual reproduction i.e.
It is expressed in the DNA of the plant. See
- 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. Common
characteristics of members of a genus are the
similarities of flowers and fruits. The plural is
For example, in the name
sieboldiana, Hosta is
the genus name while sieboldiana is an example of a
The proper format is that the genus
name is always capitalized and in italics if in print or
underlined if hand written.
- growth oriented with respect to the force
of gravity. A hormone regulated response of stems and
roots to gravity. It is why most plant roots grow down
into the earth while the stems grow upwards.
- refers to the initiation of active growth in a seed
which occurs when the initial root and stem emerge. In
fungi, it is
when the germ tube emerges from the spore.
- a collection of genetically diverse plants,
including wild specimens, which can be used to improve
future cultivated plants through cross breeding
- according to the
The American Hosta Society, there are
five size categories of
hostas are those where the
mound reaches a height of over 28 inches and an area of greater
than 144 square inches. Hostas of this size
are also occasionally called specimen size.
(gibberellic acid) a naturally occurring growth
stimulates stem elongation. In some cases, plants that
are grown as standards such as
Pelargoniums, have stems that were treated with
- generally refers to the destruction of the
layer around the circumference of a trunk or branch.
This can occur when a notch is cut through the bark of a
tree with an ax or saw or other physical damage. The cambium layer is broken and
interrupted with stops the production of new vascular
tissue resulting in death. Other things that can girdle
a tree include borer
insects (Emerald ash borer) and,
- trees grown in containers will occasionally develop a
root that begins to wrap around the circumference of the
pot. If this root is not cut at the time of
transplanting, it will continue to curl around the base
of the tree and will grow in girth. As the tree trunk
also grows in girth, eventually, the root will start to
strangle the trunk and will interrupt the
A tree with a girdling root may not show any symptoms
for many years after being transplanted. Then, it will
begin to lose vigor and decline. The tree will develop
fewer and fewer leaves and branches will die. Over time,
the entire tree may also die. This is most common on
shallow rooted trees such as
- describes a smooth, hairless
- a glaucous leaf or stem has a
waxy coating or
bloom which produces a whitish to blue coloring
of leaves or needles. As the growing season progresses, the coating
may rub or wash off especially in hot, dry conditions. Many blue
hostas will turn green by the end of the summer. This
does not hurt the plant but may change the color
design combinations in the garden.
this is the active ingredient in many common
including RoundUp, KleenUp, Rodeo and others. It is a
herbicide with very little
carryover. It must be applied to actively growing, green
plant tissue and it kills plants by preventing the
propagation method in which a scion (stem piece or
is inserted into a rootstock
so that their cambium layers align and they grow together to
form a new plant. If the cambium layers are not properly
aligned or it is allowed to dry out, the graft will
the point where the scion and
rootstock (stock) are
joined together during grafting.
- a temporary, cover crop of plants such as certain
grains, grasses or legumes that is incorporated (buried) into the soil to
nutrients and organic matter for succeeding crops.
- a plant whose major roll is to blanket an area of soil
with foliage. They often have the characteristic of
being able to spread by rhizomes or seeds to rapidly
fill the area. See invasive.
- in this context, a media or medium, refers to the
mixture of particles in which seeds germinate or plants
are grown (usually in containers). Although it could be
a mixture of soils, this usually refers to soilless
mixtures used for pot grown plants in greenhouses. This media will
consist of various proportions of
compost and other materials.
- either a natural or synthetic compound that controls
or modifies the growth process of a plant or
plants, these may be used to keep flowering plants small
during greenhouse production. Other regulators such as
gibberellin may be used to
make stems artificially tall.
insecticides act by
preventing the insect from moving through its natural
growth cycles resulting in its death.
- the soil-inhabiting larva of many
beetles. Some grubs
stay in the soil for one year before becoming beetles
while others may take up to 3 years to mature. European
chafer grubs have caused widespread damage to
Japanese beetle grubs will cause damage in irrigated
- one of a pair of cells surrounding a
stoma usually located on the
bottom of leaves. These allow the stoma to open or close to
regulate the water loss through the leaves.
Lenticels are similar openings often found on stems
but they do
not have guard cells so they stay open all the time.
- oozing of plant sap, often from a plant wound or
canker. Gummosis may occur as a result of infection or
insect infestation. This is common on peach trees.
- this refers to a water soaked area of a leaf caused by
the excessive uptake of water by a plant. This is more
common on indoor plants when they are moved from a high
humidity situation to a low humidity area.
- a plant with seeds not
enclosed in an ovary. They are also called
plants and include the conifers
which are plants with generally needlelike foliage and
which usually bearing cones