Weed Management in Turf + Landscape design

how many acres of turf are in U.S.?

40 mil

types of turf, and why it matters?

atheletic, golf course, residential

use dictates level of care /management

weeds ivade areas wehre growth is limited - 

bare spots

wet areas

dry patches

______ managed turf has more weeds

poorly

sword

lush evenly mowed area in turf

____ methods for weed management have the greatest impact

cultural

turf types

cool season - kentucky bluegrass, fescue, bentgrass

warm season - bermudagrass, centipedegrass, zoysea

influence of soil types on turf growth

water holding capacity

rooting depth

cool season grass in summer- problem

gets heat stressed

prevent by mixing cool and warm season grasses

cultural weed management

• plant clean seed

• dense stand of adapted specie/varieties (sun vs shade areas)

• proper

  • fertility

  • watering frequency and amount

  • drainage

  • mowing frequency and height

• disease and insect control

REMEMBER IN TURF THIS IS THE MOST IMPORTANT CONTROL CATEGORY

how much of turf blade should you mow off at any given time?

1/3

what is properly managed turfgrass

turf that is fertilized at the proper time with the proper rate and proper technique

• rate, time, technique

mechanical weed controls:

mowing, digging, pulling

chemical weed controls:

based on weed emergence and growth

• timing

  • preemergence

  • postemergence

• formulations

  • granules are best for homeowner apps

mowing height importance

heights change color of turf? weeds scalp fescue and crabgrass germinates-

biological controls:

rare

major weeds:

annual bluegrass

crabgrass

foxtail

goosegrass

what does preemergence control and when is it sprayed

crabgrass, sprayed earl april

(crabgrass germinates between 49-53F)

common herbicides used

bensulide (grasses)

DCPA (grasses, chickweed, purslane)

Benefin (grasses)

siduron (new seedlings)

benefin 

Pendimehtlin

Prodiamine

Diothiopyr

easier to kill perennial in fall than in the spring, why?

2 quts spring 1 qt in fall

because it is hard to push herbicide down in the spring when all the photosynthetic products stored in rhizome are being pushed upward

in the spring the plant is storing the carbs in the structures and will readily take the herbicide down with it

postemergence gets sprayed when?

may through end of summer

Postemergence chemicals:

DSMA MSMA controls yellow nutsedge (MSMA phased out in 2009)

Fenoxapren - crabgrass

halosulfuron - nutsedge

quinclorac - crabgrass and broadleaf

major boradleaf weeds

chickweed, knotweed, docks, plantain, dandelion, yarrow, thistles, red sorrel, shepherds purse, purslane

cool season preemergence chemicals:

isoxaben

bendimethalin

cool season preemergence (app time, what controlled, why would we?)

• fall apps best

• perennial and annuals controlled at once

  • turf will re-invade bare spots and early spring

postemergence chemicals

2,4-D, MCPA, and dicamba mixtures

2,4-D and triclopyr

Triclopyr and clopyralid

bentazon (yellow nutsedge)

weed problems;

ANNUAL

crabgrass, clover, henbit, pigweed, purslane, spurge

BIENNIAL

burdock

PERENNIAL

honeysuckle, dandelion, nutsedge

how to manage

learn what you have first!!!

prevention techniques -

weed barrier mat (nutsedge can poke through) (weed seed introduced on the top)

mulch

newspaper

rock (changed less often, just spray herbicide over) (they heat up in the summer)

bark

straw

pine straw

Before planting management

• site assessment

  • ID weed species near spot

• site preparation

  • kill exhisting weeds, roundup

  • remove waste and grade

• define site

  • trees and shrubs, ground cover, annual flowers, perennial and mixed planting beds

• dont introduce weeds

• encourage rapid establishment of desired plants

weed removal methods

mowing/trimming

spraying (roundup)

hand pull

cultivating

flaming

can plants develop into a viable seed if pulled before maturity?

yes, even at 50% maturity

downsides of mechanical controls

strenuous to hand pull (most employed summer  job)

cultivating use hoe shovel or trowel

mowing takes time

mulch is thick and can be expensive

preventing weeds in landscape

install landscape fabric

smother with mulch

apply pre-emerge herbicides

deprive weeds of water

pull weeds when seen

flame weeds

spot spray with herbicidestr

do we like spraying herbicides?

no recommend just doing roundup spot spraying

weed mistakes

• leave flowers on ground

• pile mulch over fabric

• mulch contains weed seeds

• toss weed seed into compost

• break perennial roots when trying to dig out

  • plant weeds with new trees

pre-emergence landscape herbicides

atrazine, broadstar, casoron

broadleaves and some grasses

postemergence landscape herbicides

`finale, envoy, fusilade II , roundup pro

annual and perenial grasses, broadleaves (most)

mechanical methods

the most common is pulling weeds (rhizomes don’t always come)

sometimes need to till to get close to the plant base