The Earth & Turf Model 320 Vineyard Special is especially useful in spreading compost in vineyards, the benefits of which are explained in detail in an article entitled “Compost and Mulch – Investing in vineyard health” by Christy Porter, California Integrated Waste Management Board, Sacramento, CA, that appeared in WINEGROWING magazine, November/December, 1998. A few brief excerpts from that article will explain:

“Will Bakx, a soil scientist for Sonoma Compost in Petaluma, CA, produces high-quality compost from urban yard trimmings. Many vineyard managers who apply compost and mulch after harvest are finding these products to be useful components of their vineyard floor management program. While some vineyard managers purchase these soil amendments, others make their own compost from grape pomace. Either way compost and mulch are products that result from recycling materials that might otherwise be wasted. As many communities collect yard trimmings at the curb to reduce organic materials going to landfills, these materials are being transformed into valuable soil amendments by producers such as Bakx. Growers and researchers alike are discovering the benefits of these recycled soil amendments.”

“After three consecutive years, the study at Robert Mondavi Winery’s Tokolon Z block found that blocks with compost applied had increased yields of up to 0.9 tons per acre, while the fruit quality remained the same. Application rates for the study ranged from two to eight tons per acre with the 0.9 tons per acre increase in yield occurring in the eight-tons-per-acre treatment.

Cost of the compost at $24 per ton applied at Tokolon was recovered by an increased yield valued at $1,350 per acre. Since the trial ended in 1995, about four tons per acre of compost has been applied annually to 20 acres.”

“While many vineyards use straw or cover crops for erosion control, mulch made from urban yard trimmings can be a cost-effective alternative. Mulch is usually used for erosion control, weed suppression, and water retention. Compost improves soil tilth, adds beneficial microorganisms, and may be used as a slow-release source of nutrients. Mulch consists of yard trimmings that are ground and then screened to a uniform particle size. Unlike compost, mulch does not undergo extensive processing to decompose the material and is, therefore, usually less expensive. It is generally applied as a top dressing and slowly decomposes over time.”

“UC Cooperative Extension advisor Ben Faber in Ventura County, CA, has been conducting a demonstration study to examine the effectiveness of mulch and cover crops for erosion control in lemon orchards. ‘Preliminary results indicate that both mulch and cover crops are effective as weed suppression and erosion control methods,’ reports Faber. As vineyards continue to expand onto hillsides, mulch is a feasible tool for erosion control.”

“Clyde Elmore, a UC Cooperative Extension weed advisor, recently spoke at Foothill Grape Day in the Placerville area regarding vineyard floor management. Elmore discussed his research on the use of mulch for weed control. From his trials, Elmore concluded, ‘Green-waste wood chips give good weed control. The mulch was persistent in the field and should give long-term weed-control benefits. Because it may last for more than one season, the short-term direct cost is not the best way to evaluate this product. However, many perennial weeds such as field bindweed are not controlled well with organic mulches. Depending on the coarseness of the mulch, two to six inches of material is needed to control most annual weeds.”

“At Pina Vineyard Management, Mr. White applies compost for weed control in his vineyards. He is perfecting a vine row applicator with the hopes to suppress weeds with compost application right next to the vines. ‘We find this is the most effective way of applying the com- post. The chute will deposit the compost right where we want it and give us a more concentrated application than broad-scale spreading.’” (No doubt the Earth & Turf Model 320 Vineyard Special would be an ideal alternative to his vine row applicator, and at a very reasonable price.)

“Spreading compost is a beneficial practice to consider. If your vineyard could benefit from improved soil structure, added beneficial microbes, improved moisture retention, and better erosion control, consider making or purchasing compost and mulch. Compost and mulch can be important long-term investments in the health of your vineyard.”