About Weeds The term “weeds” is a relative one, and it is ... · PDF fileAn...

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About Weeds What are weeds? The term “weeds” is a relative one, and it is quite difficult to draw a line that clearly defines which plants are desirable and which should be classed as pests. We could probably say, without fear of contradiction, that a weed is any plant that grows where we do not wish it to grow. Many plants which might be desirable in some locations, have become serious pests when allowed to spread. White clover for instance, is a plant that is quite useful in lawn building, but which becomes a weed when it moves into a strawberry patch or garden. The chief attribute of all weeds is there rugged persistence, and the study of them will quickly show why they have always harassed gardeners. CATEGORIES OF WEEDS Annuals, which complete their life cycles in one year Biennials, which require two years Perennials which live on indefinitely and produce seeds year after year

• Summer Annual vs Winter Annual – re germination of seeds

• Spring/Summer/Fall – re time of flowering

• Root Type – Shallow/Tap Root/Runners QUANITY OF SEEDS While a corn plant may produce 1000 seeds and a wheat plant a hundred, some of the weeds that grow in competition with them may produce seeds by tens of thousands. A healthy cocklebur may produce 10,000 seeds and a Russian thistle well over a million. An Evening Primrose can completely take over a garden with each plant capable of producing 1 M seeds. SEED DISPERSAL - It is helpful to be aware of how plants distribute their seeds. Gravity – most plants

Wind - such as Dandelions and Ragworts Ballistic dispersal - by exploding capsules that are capable of shooting their seeds considerable distances, such as Mustards, and Bittercress Attach – sticky appendages on their seeds - Cocklebur, Tick-Seed Sunflower Fruit - Eating without digesting – by putting seeds into a fruit, that is edible at least by animals, such as Pokeweed and Poison Ivy

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LENGTH OF VIABILITY To further complicate matters, weed seeds have, in many cases, the ability to remain alive in the soil for many years until conditions favorable to their growth are present. WEED GOOD SIDE Although weeds compete with our cultivated plants in many ways, they do have some good points on the credit side. They afford food and shelter for many birds and small animals. They quickly cover a bare field no matter how poor the soil, they prevent erosion. Many of them add to the beauty of the out-of-doors with colorful flowers, and many of them produce valuable drugs and chemicals WAYS OF CONTROLLING Pulling/Hoeing – a lot of weeds that have no taproot can be totally destroyed by getting rid of top growth before they go to seed.

Digging/Grubbing (If tap root) – get the roots – easier to do when soil is soaked and the weeds are young Herbicides Pre-Emergent – prevent seed germination. If an annual, the pre-emergent will keep the seeds from last year’s plants from sprouting. Use Preen/Corn Gluten Meal in spring when soil temperatures reach 64 to 65 degrees Fahrenheit it is time to spread or spray a pre-emergence herbicide. Timing is important. The pre-emergence herbicide must be applied just before the germination of new seed, just as the ground reaches 65 degrees. Use again in the early fall for winter annuals Post-Emergent – Non Selective/Contact/Systemic Non Selective/Selective - Non-selective herbicides may kill any plant that it comes in contact with Contact – such as vinegar and hot water. Vinegar – non-selective – contact – can use household concentration but need to do repeated applications – a 20% concentration or higher is more effective – above 10% can burn your skin - use with sticking agent. Use ½ gallon of vinegar + ½ cup of salt + 2 tablespoons of dish soap. The vinegar + salt solution, since it doesn’t move throughout the plant, will not be effective on perennial weeds, except thru repeated use. It will burn off the top growth of perennials (which may be desirable), but it will not provide long-term control.

Boiling Water is also considered a good contact herbicide but hard to generate in

a remote garden.

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Systemic – applied to top but flows to roots. Usually cheapest and most effective is Glyphosate (Round-Up) – safer than most organic herbicides – probable human carcinogen (so are red meat and hair spray) – swimming in heavily chlorinated pools are more toxic – safe if used wisely

Solarization covering with black plastic or exposing roots to sun Flaming/Burning – using a propane torch – hard to be very selective. COST OF CONTROL On the other hand, it is estimated that these common weeds cost us over $3 billion annually in attempting to control them. NEED TO REMEMBER

KNOW YOUR WEED – Shallow or tap root Weed when ground is WET for easier results Weed BEFORE they go to SEED Pieces of some plants can RE-GENERATE

WIRE GRASS

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WIRE GRASS PLANT

CRAB GRASS WITH ROOTS

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CRAB GRASS BASE

CRAB GRASS SEED

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GOOSE GRASS BASE

GOOSE GRASS SEEDS

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FOXTAIL GRASS

FOXTAIL GRASS – DANGER

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SEDGE - SEED HEADS

MUGWORT – RWGC Enemy #1

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MUGWORT FOILAGE

MUGWORT – WHOLE PLANT

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BEDSTRAW

BEDSTRAW CROWD

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BEDSTRAW CLOSEUP

BROADLEAF PLANTAIN

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PLAINTAIN – HEALING

PLANTAIN – NARROW LEAF

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PLANTAIN – PLAYING

Mature Pokeweed With Fruit

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Young Pokeweed

RAGWEED

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RAGWEED

RAGWEED

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RAGWEED LEAF

GOLDENROD vs RAGWEED

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BINDWEED

Bindweed and Flower

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COMMON EVENING PRIMROSE

Evening Primrose Pods

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Evening Primrose Roots

Evening Primrose Rosettes

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MEXICAN EVENING PRIMROSE

MEXICAN PRIMROSE LEAVES

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MEXICAN PRIMROSE CROWD

SMARTWEED (Knotweed)

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Smartweed – Crowd

Smartweed – Leaf

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WILD ONIONS

WILD ONION – Bulbs

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MARSH MALLOW

Marsh Mallow – Pod

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WILD STRAWBERRY

Wild Strawberry Plant

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Wild Strawberry – Size

CINQUEFOIL

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Cinquefoil – Off & Running

CINQUEFOIL – LEAF

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DAISY FLEABANE

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PENNYCRESS MATURE

GROUNDSEL LEAVES

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GROUNDSEL FLOWER

TANSY RAGWORT

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TANSY RAGWORT SEEDS

BITTERCRESS

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CHICKWEED SPECIES

CHICKWEED

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SPEEDWELL

SPEEDWELL LEAVES

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BUGLE/AJUGA

BUGLE CROWD

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BUGLE LEAF

GROUND IVY

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GROUND IVY – CLOSEUP

HENBIT – EVERYWHERE IN SPRING

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HENBIT IS RWGC ENEMY #2

PURSLANE

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PURSLANE

PURSLANE SEEDS

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SPOTTED SURGE

SPURGE FLOWERS

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SOME OF THE WEEDS YOU WILL SEE BUT HAVE NOT BEEN COVERED Dandelion Wild Mustard Garlic Mustard Clover Cocklebur Poison Ivy Tick-Seed Sunflower Vetch If you want to find out what these look like or get more information on the “weeds”, that were covered GOOGLE the plant name.