Transcript Weed Identification

National Railroad
Contractors Association
Plant Biology
 Plant
growth stages
 Plant
life cycles
 Plant
types
 Plant
construction
 Plant
growth factors
 Seedling
– Small succulent – Stage most
easily controlled
 Vegetative
– Rapid growth
 Reproductive
 Mature
– Flowers and seeds
– Post reproductive
 Annual
 Biennial
 Perennial
 Annuals
complete their life cycle in one
year.
 Winter
annuals
 Summer
annuals
 Seeds
germinate late summer to early
fall,
 Flower
and produce seed in mid-to late
spring, and
 Die
the next summer.
 Seeds
germinate in the spring,
 Flower, produce
seeds mid-to late
summer, and
 Die
in the fall.
 Ex-most
everything
 Live
for two growing seasons.
 Seeds germinate in spring, summer, or fall of
first year.
 Plants over winter as basal rosette with storage
root.
 After exposure to cold, plants flower and
produce seeds in summer of second year.
 Die in the fall.
 Produce
vegetative structure that allows
them to live more than two years.
• Overwinters by a perennial root
• Reproduce entirely by seed
 Overwinters
 Produces
new plants from reproductive
structures
 Most
also reproduce from seed
Stolons
horizontal above
ground stems
Creeping roots
 Underground root
modified for food storage,
vegetative reproduction
 Grows
deep in soil
 Resistant to control
Soil line
Rhizomes
horizontal
underground
stems
http://www.wildlifeanalysis.org/movabletype/archives/rhizome.jpg
Tubers
thick underground
stems on the ends of
rhizomes
Bulbs
modified underground leaf tissue
Reproducing parts
 Grasses/Sedges
 Broadleaves
 Vines
 Trees
 Ferns
(forbs)
• One leaf at germination
• Fibrous root system
•Growing point at soil surface
•Narrow upright leaves
•Parallel veins running length of leaf
• 2 leaves at germination
• Broadleaves
• Netted veins
• Growing points all over
• Tap root system
 Plant
with a weak stem
that needs support from
climbing, twining, or
creeping along a surface
 Trees - perennial, single main stem or
trunk
 Shrubs - perennial, more than one
principal stem, shorter than trees
 Largest
group of
seedless, vascular
plants
 Grow
in moist
places
 New
fronds (leaf)
form from rhizome
 Xylem
– moves herbicide, water,
nutrients
up from roots
 Phloem
– moves
herbicide
from foliage down to roots
 Grasses
have
vascular bundles
that contain xylem
and phloem in one
unit
Water
 Transports nutrients and herbicides from
root to leaf
 Moves sugars and foliar applied
herbicides from leaf to roots
 Water
 Rain
is key in photosynthesis
carries herbicide to root zone
Soil
Soil texture
depends on
percentages of
sand, silt, clay
Soil
Coarse or light soil
is high in sand
Soil
Fine or heavy soils
are high in clay
Soil
Dark soils are high in organic matter (OM),
decaying plants and animals.
As Clay
As OM
As Sand
Adsorption
Adsorption
Adsorption
Leaching
Leaching
Leaching
Herbicide Use
Herbicide Use
Herbicide Use
Application Rate
Application Rate
Application Rate
Temperature
As Temperature
Warm soils
Plant activity
Persistence of
herbicide
Speed of herbicide
effect