1. Low Impact Weed Control Mulches Cheryl Wilen Area IPM Advisor UCCE/UC IPM

2. Stages for Weed Management  Planning  Prevention  Control  Restoration

3. Questions About Landscape Mulches Is mulch the same as compost? What is a mulch? Do termites eat mulch? How long do various mulches last? What’s that stuff growing in my mulch? How do they change soil?

4. Mulch  A material that covers the soil surface.  Shades the ground and physically hinders germinating weed seedlings.  Mechanical method of weed management

5. Selection of a specific mulch Characteristics Availability Cost How often it needs to be replenished Non toxic to plants Easy to apply Free from pathogens and weed seed Not a nitrogen drain How to Choose

6. LOTS OF CHOICES!!  Natural Bark Grass clippings Leaf mold Manure Wood chips  Synthetic Non-woven c loth Plastic film Woven cloth

7. http://www.gardenplace.com/content/calculator/mulch_calc.html# Search: Mulch calculator

8. Is Mulch the Same as Compost? Mulch is a use. Compost is a process.

9. Benefits of Landscape Mulch Annual weed control Soil improvement Prevents erosion Helps improve soil structure Improves water infiltration Prevents water loss by evaporation

10. Soil Improvement Erosion Control A thin layer of mulch on the soil surface reduces the washing away of soil particles by rushing water. Mulches prevents raindrops from splashing on the soil surface. Increases organic matter from breakdown A mulch layer on the soil surface allows the soil to soak up more water.

11. Evaporation Reduction A 3-inch layer of mulch on the soil surface dries much faster than the soil below it This prevents water from moving into air.

12. Breakdown A 3-inch layer of mulch on the soil surface keeps most annual weed seedlings from coming through. Mulch settles and gradually rots Add additional layers

13. DISADVANTAGES OF MULCHING Some mulches can cause a temporary, decrease in soil nitrogen Some mulching practices are labor intensive Bad mulches are “sour” and phytotoxic May have insects, pathogens No perennial weed control

14. More = Better

15. What’s that growing in my mulch? Bird’s nest fungi Slime molds Mushrooms

16. Termites Would subterranean termites survive on mulch? Would subterranean termites eat mulch? Mulch provides better habitat than food Should keep mulch about 18” away from wood structures Note: probably not an issue for drywood termites

17. Fabric Mulches Fabric thickness affects the degree of weed suppression. Prevents light penetration.

18. Rose Vigor (approx. 5 months after transplanting) 0=dead, 10=highly vigorous

19. Agricultural Mulch Basic colors used (black, green, red) Black Most widely used Usually embossed for strength Cheapest Warms soil by contact Plastic Films

21. Rubber Mulch - a "permanent" mulch that doesn't rot, dissolve into the ground or wash away from rain. Made from recycled rubber truck tires, lasting ten years

22. PHYSICAL CONTROL OF PESTS: USE OF MULCHES

23. MULCHES MAY BE USED TO: MANIPULATE TEMPERATURE MANIPULATE LIGHT MANIPULATE SOIL MOISTURE OTHER EFFECTS

24. REDUCE INSECT FEEDING DAMAGE AND TRANSMISSION OF DISEASES USING REFLECTIVE MULCH

31. MODES OF ACTION: Light reflectionLight reflection Other?Other?

32. Insect Feeding Behavior