Pine Straw as a Ground Cover Mulch

Introduction

Pine straw popularity is fairly recent in Texas, but it has been a popular landscape ground cover throughout the South for the last 25 years. In fact, it is one of the most widely used mulches for all size projects ranging from residential flower beds to industrial complexes and highway landscapes. Landscapers, building contractors, and homeowners have discovered that pine straw has superior properties over other mulches. Unlike other dry organic mulches such as pine bark, leaves, grass clippings, and peat moss, pine straw helps provide favorable growing conditions and stimulates healthy plant development because it:

• Insulates tender roots from temperature extremes keeping the soil warm during cold spells and cool during warm spells,
• Conserves soil moisture by reducing water evaporation rates and moisture loss,
• Encourages water infiltration into the soil and reduces runoff,
• Eliminates erosion caused by wind and rain-splash impact,
• Protects against soil compaction by reducing the rain impact directly on the surface, and
• Aids in promoting favorable soil tilth for healthy root growth.

Pine straw may also hinder the establishment of weeds and soil-borne diseases. Since pine needles interlock even on landscapes with considerable slope, pine straw will not wash out of beds like some other mulches. Pine straw also remains loose and friable and does not form a top crust like grass clippings, leaves, and some wood mulches. Loose mulch allows water to infiltrate readily into the soil for plant availability and avoids wasteful irrigation runoff. The large air pockets, however, help prevent it from remaining excessively wet and damaging roots. Lastly, the fine texture and uniform color of pine straw is simply more aesthetically pleasing to some users. The attractive, earthy facade brings out the color, contrast and texture of landscapes.

Pine straw serves as a quality much for landscapes and gardens.

Types of Pine Straw Bales

Four species of southern yellow pines occur in Texas. Slash and longleaf pine are primarily distributed in Southeast Texas. Shortleaf is found chiefly in Northeast Texas, and loblolly is distributed evenly throughout all of East Texas. Listed in order of needle length from longest to shortest, they are: longleaf, slash, loblolly and shortleaf. Regardless of the species, each makes a first-rate mulch; however, shortleaf is too short to bale but might be marketable in bags or by shrink-wrapping bales.

Pine straw is sold in round bales, square bales, and bags all weighing from 25 to 50 pounds and yields 3 to 6 cubic feet. Square bales often measure 14 by 14 by 26 inches. Round bales measure18 inches in diameter and 26 inches in length. Customers tend to prefer smaller, lighter bales. Collection points that buy loose straw from small growers and homeowners are distributed throughout East Texas.

A 40 pound bale will cover about 100 square feet.

About three inches of pine straw, that settles to 1.5 inches, should be used in new applications. That equals to half a pound of straw per square foot. An additional inch per year is required to maintain the proper depth. Compared to alternative organic mulch, pine straw is typically the least expensive option saving from $1.60 to $4.60 per 10 ft by 10 ft bed.

Table 1. Cost comparison of using Texas Pine Straw mulch versus traditional mulches. Comparsion taken from East Texas Lowe’s Home Improvement store on February 5, 2002. Bed thickness used in all examples is 2 inches.