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43 Cards in this Set
- Front
- Back
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ORIGIN OF WEEDS
weeds are either native or ... |
introduced
knowing whether a weed is native or not helps control it |
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NATIVE WEEDS
have historic origins NOT brought in by people have natural enemies competition from other plants enviromental ways that hold many NATIVE weeds in check (native weeds are rarely a problem!!!) ***************** INTRODUCED PLANTS Where did they come from? |
unintentionally brought in from elsewhere (Europe, Eurasia)
Most problem weeds are introduced weeds *************************** |
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ESCAPED PLANTS
Intentionally brought in as crops forage ornamentals but spread beyond intended areas. so what? |
there are no natural mechanisms to control these escaped plants in a new enviroment.
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HOW WEEDS SPREAD
How are weeds spread? |
when seeds or growing plant parts are moved or carried somewhere
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Seeds can spread in various ways.
wind water animals people! how? |
seed shapes and design!
seeds that move thru air have parashoots, animal moving seeds have burs or hooks, etc |
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WIND
wind carries seeds with parachute things OR the entire plants rolls around throwing off seeds WATER how does water distribute weeds? |
WATER from rain or irrigation or runoff move seeds.
Seeds have oil on them that help them float in water! |
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MAMMALS BIRDS HUMANS
all can carry seeds off and drop them in new areas. How? |
work trucks
mowers turf cars contaminated topsoil animal droppings hair or feathers of animals peoples clothing or bodies |
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WEED ESTABLISHMENT & PERSISTENCE
weeds become a problem in turf and ornamental beds when the ground is disturbed enough for weeds to get established. Usually where? |
construction sites
heavy foot traffic areas scalped turf edges of planting |
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Weeds don't compete well with established growing turf or ornamental plantings. BUT ...
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if weeds are established, and allowed to go to seed, this produces LARGE numbers of seed ensuring their survival
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Weed seeds can stay dormant int the soil for almost ever. Because of this, weed management is a ...
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long term process
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WEED CLASSIFICATION & LIFE CYCLES
You dont have to know a weed species to control it but it IS crucial you know ... |
if a weed is:
a grass or broadleaf plant understand its life cycle to help select a successful control method |
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Accurately id weed is first step in effective weed control program.
some common weeds no problem but what about all the others? |
knowing new weed species is difficult and requires a working knowledge of a plants anatomy and classification
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STRUCTURAL CHARACTERISITCS
of weeds are one way to classify a plant (weed) what are structural characteristics? |
2 groups for plant structure
grasses broadleaves |
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GRASSES & SEDGES
have ... |
only one SEED leaf.
leaves are narrow and upright Leaf veins run parallel to leaf margins. Roots are fine & branching (fibrous) Again this is GRASSES & SEDGES |
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GRASSES & SEDGES
how are they different? grass = crabgrass quackgrass barnyardgrass SEDGES = Yellow nutsedge |
SEDGES have triangle shaped stems
GRASSES have round or oval stems Both have 1 seed leaf. Leaves are narrow & upright Leaves extend in 3 directions Sedge is a grass!!! |
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2 MAJOR PLANT GROUPS
grasses and broadleaves. Broadleaves are? |
plants
trees shrubs that have 2 seed leaves. Leaves generally are broad w/ netlike veins Rood system is coarse, often w/ a strong taproot. |
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HERBACEOUS
What is herbaceous? |
Herbaceous usually refers to perennials but a dandylion is a herbaceous plant.
Herbaceous plants are plants with non-woody stems. all annuals are berbaceous but not all herbaceous are annuals perennials are: 1) herbaceous 2)woody perennials like trees/shrubs Technically, a herbaceous plant, one that does not form a woody stem. More popularly, herbs are “useful” plants, grown for their fragrance, medicinal properties, or culinary attributes. Under this definition, an herb may be herbaceous, like parsley, or woody, like rosemary. |
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HERBACEOUS (again, do not regrow from woody tissue above the ground).
Broadleaf plants can be herbaceous or they may be ... |
woody like trees or shrubs
Dandylions knotweed plantain typical herbaceoius broadleaf weeds. |
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Herbaceous plants like a shrub have several stems (a woody weed) or they can have a single stem like a ...
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trunk of a tree and generally grow taller than 10 feet.
shrubs usually don't grow taller than 10 feet. So, woody weeds Herbaceous shrubs and trees as weeds. |
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PLANT LIFE CYCLE?
what is plant life cycle? |
PLANT LIFE CYCLE is another weed classification.
You need to know a plants life cycle to understand when it can be vulnerable at certain growth stages! seedlings vegetative flower maturity Plants are classified by life cyles! ANNUALS BIENNIALS PERENNIALS |
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Why would we pest control guys be intrested in a plant's life cycle as a weed classificiation?
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Certain times in a plants life cycle they are especially vulnerable to control strategies. We can target these plants at certain PLANT GROWTH STAGES.
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What are the plant growth stages?
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seedling
vegetative flower maturity Again, these are plant growth stages. They are also the plants life cycle. |
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What is normally the easiest plant cycle plant to control?
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annuals are normally easiest to control
BUT they are continous problem b/c of all the dormant seed their fast growth hi seed production |
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Annuals live 12 months or less and there are summer annuals and ....
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winter annuals.
Normally annuals are the easiest to control BUT... they continue to be a problem because of abundance of seeds, they grow fast, and have a high seed production. So, it can cost MORE to control annuals than perennials! due to high number of different species. |
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What is the strategy of controlling annuals?
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long term control of annuals is ...
stopping seed production |
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Again, what are the 2 types of annuals?
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summer
winter annuals |
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GERMINATE is?
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to sprout from seed
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summer annual plants germinate
spring summer. grow flower set seed die before ... |
winter.
seeds lie dormant in soil until next spring or several springs later. |
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Annuals grow vegetative state in spring
Annuals flower in late spring and go to seed when? |
Annuals go to seed in mid summer and die in the fall
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When do winter annuals germinate?
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late summer to early winter.
(they over winter in a vegetative stage). Again, what is the life cyle? germinate vegetative growth flower set seed die |
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BIENNIAL PLANTS
complete their life cycle? |
within 2 years
First year plant forms BASAL leaves (rosette) and root system (taproot) 2nd year plant flowers matures dies (there are NO biennal grasses or sedges) ***************************** |
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Life cycle of a BIENNIAL is 2 years. First year plant forms basal leaves (rosette) and large root system (taproot). what happens second year?
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the plant flowers, maturs, dies.
(There are NO biennial grasses or sedges) |
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People can confuse biennials with winter annuals. How does this happen?
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winter annuals have life during 2 calender years! And 2 seasons! BUT life cycle is still 12 months or less.
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Biennial weeds are usually easier to kill when?
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easier to kill the first year, BUT finding their rosette is easily overlooked! You have to find them to control them.
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What are some common Biennials?
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common mullein
common burdock bull thistle poison hemlock tansy ragwort wild carrot |
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Perennials
live more than 2 years some live almost indefinetly resprouting from vegetative plant parts. This is what makes them hard to kill! ******************************They are PERSISTENT! how? |
resprouting roots
rhizomes stolons tubers plant fragments Perennials spread rapidly and are difficult as hell to control. |
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Whats the control strategy with Perennials?
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do not let perennial seedlings become established. Most perennials reproduce by seed. MOST PERENNIALS REPRODUCE BY SEED. But spread vegetatively too.
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Perennials are classified according to ...
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how they spread
simple creeping |
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SIMPLE PERENNIALS
Perennials are either simple or creeping. What is a simple perennial? |
Simple Perennials resprout from crown buds on the taproot
Simple perennials also spread by seed Its the taproot that will resprout so you have to pull the whole plant up. |
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Creeping perennials reproduce by ...
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creeping roots
creeping aboveground stems (stolons) creeping belowground stems (rhizomes) reproduce by seed also. So creeping roots above or below ground are creeping perennial reproduction. |
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Quackgrass and Johnsongrass are examples of
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underground stem creeping perennials.
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Canada thistle
field bindweed sprout new shoots from creeping roots. Bentgrass ground ivy sprout new plants from ... |
aboveground runners or stolons.
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What plant, once infested are the most difficult group to control?
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creeping perennials are the most difficult to control once they infest an area.
Control might require: repeated cultivation mowing herbicide apps combo of any of this |
