Weeds Will Be With Us So, How do you correctly identify a weed? we - PDF document

Weeds Will Be With Us – So, How do you correctly identify a weed? we need to develop weed Compare to a photo Remember weeds can appear different management plans. due to site conditions Easiest to do when plant is flowering The First Step: Weed ID – Keys to Identification Its more than a name Send a sample to the University Extension Weed Scientists Landscape Weed Control – JC Neal, NCSU Identification Resources How to order: For Piedmont and Coastal Plains Weeds of Southern Turfgrass Identifying Seedling and Mature Weeds in Publication Distributions Center the Southeastern US IFAS Building 664 Weeds of Southern Turfgrass P. O. Box 110011 Mountains University of Florida Weeds of the Northeast Gainesville, FL 32611 Weeds of Southern Turfgrass (352-392-1764) On-line: Turffiles http://www.turffiles.ncsu.edu/turfid/itemselector.aspx PS: I think Clemson has some too) Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU How to order: How to send a sample for ID Fresh samples: moisten sample; wrap in Weeds of the Northeast DRY paper towel; put in a zip-lock bag and Cornell University Press mail on Monday or Tuesday to the P. O. Box 6525 appropriate specialist Ithaca, NY 14851-6525 If you cannot send it right away (or if you 607-277-2211 get the sample on Thursday or Friday: Lay flat on between newspaper; press. $29.95 plus $5 shipping Mail the dried, pressed sample to the appropriate specialist Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 1

Step 2 -- Develop a weed How NOT to send a weed sample management plan Understand the weed and its life cycle Weed management options Optimum time to control the pest Proper application Too Dry Too Wet Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Life cycle of an annual weed Life cycle of a winter annual weed Summer Fall Plant Plant Seed Seed dies dies Seedling Seedling Plant Plant sets sets Plant Plant seed seed flowers flowers Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Life cycle of a summer annual weed Common Spring Fall Plant winter annual Seed dies Seedling weeds Plant sets Plant seed flowers Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 2

Life cycle of a perennial weed Common Summer Annual Weeds Roots/ rhizomes spread Seedling Seed Plant Over-winters Plant J. Derr Flowers Plant sets New plant Seed Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Perennial Weeds Reproduce By: Some common perennial weeds Seeds Tubers Bulbs Rhizomes Stolons Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Types of Perennial Weeds Simple Perennials Simple perennials Spread by seed Creeping perennials Tap root or hardy Rhizomes fibrous root system Stolons Examples: dandelion, Creeping roots that produce shoots plantain, dogfennel, Tuberous perennials pokeweed Tap root Bulbous perennials Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 3

Creeping Perennials Stolon Tuberous Perennials Tubers are swollen, Tubers Reproduce and spread by modified stems that are Underground stems (rhizomes) often resilient to controls, Above-ground stems (stolons) spread by cultivation, and Creeping fleshy roots that produce Rhizome may persist in the soil for new shoots years. Many also reproduce by Tubers form on rhizomes seeds or other means. Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Bulbous Perennials Weeds Are Also Classified By: Cotyledons (Seed leaves) Persist through the dormant season as a bulb Wild garlic and wild onion produce bulblets, aerial bulblets, and seeds Dicot Monocot (two seed leaves) (one seed leaf) Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Monocots Monocots -- Examples One seed leaf when Grasses Sedges plant emerges Rushes Onions Long narrow leaves Garlic Lilies Parallel veins Dayflower Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 4

Grasses seedhead blade Rounded or flattened stems and Grasses are ligule sheath nodes identified by: Have fibrous root systems auricles Some have fibrous roots, rhizomes midrib collar or stolons for reproduction stolon bud leaf Growing point is below surface crown rhizome Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Ligules Vernation or Leaf Bud Rolled in the bud Folded in the bud Absent Membranous Hairy Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Auricles Ligules Absent Membranous Hairy Absent Present Clasping Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 5

Seed heads Seed heads Panicle Branched spike Spike Panicle Branched spike Spike Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Yellow and Purple Grass-Like Weeds Nutsedges ( Cyperus spp.) Sedges: Sedges have triangular “stems”. Grasses have flat or rounded “stems”. Grass-like, but “Sedges Annual and perennial species have edges” – triangular Most common and difficult to control are “stems” yellow and purple nutsedge Leaves emerge 3-ranked Wild Garlic and wild onion : hollow Spread by rhizomes and leaves have a pungent onion-like or over-winter as tubers garlic-like aroma Tubers often introduced in Wild garlic is the most common top soil Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Wild Garlic ( Allium vineale) Dicots or Broadleaf weeds � Bulbous perennial Two seed leaves (cotyledons) � Strong scent Leaves have netted veins � Reproduces by Largest group of weeds bulblets, rarely by seed Often with bright showy flowers � Emerges in the Exposed growing points winter and dies back in late ART FROM 2-2 spring or early summer Aerial bulblets Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 6

Unique Characteristics How to ID Dicots Look for: Flowers Thorns or spines Unique Characteristics Growth Habit Square or winged stems Leaf Orientation, Shape, Etc. Compound leaves Whorled leaves Milky sap Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Growth Habits Leaf Orientation Opposite J. Neal Whorled J. Neal Alternate Spreading Upright Rosette Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Simple Verses Compound Leaves Other Ways to Identify Cont. Leaf shape Leaf margin Toothed,entire,lobed, or deeply cut Petiole length Hair on leaves or other parts Pinnate Palmate Simple Compound Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 7

Leaf Shapes, tips & bases Deeply Leaf Margins lobed Entire Shallow lobes or toothed J. Ditomaso Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Hairs – Tell Me What You See? present or absent, & where? Mouseear chickweed -- Common chickweed -- Hairs on stem & leaves Hairs absent Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU Tell Me What You See? Tell Me What You See? Rosette Broad, nearly entire leaves 5 veins Flowers on spikes Broadleaf plantain Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 8

Tell Me What You See? Assignment – Weed Collection 25 common weeds Alternate leaves Press, dry and mount Deeply divided Correctly identified (dissected) Include required specimen label information leaves. Twice lobed. Due Date: October 20th Landscape Weed Control – JC Neal, NCSU Landscape Weed Control – JC Neal, NCSU 9