Q:
What is that green stuff all over the ground on campus?

A:
The green stuff is mulch material used on new seedbeds, said Ron Eckenroth, supervisor of grounds maintenance. It helps to keep moisture in the ground, control weeds and has some starter fertilizer in it. The mulch material on campus can either be PennMulch or wood fiber mulch, depending on where it is used.

Like straw, PennMulch and wood fiber mulch provide a top layer on the grass to protect the seedlings. However, these mulch materials are beneficial because they do not blow around like straw does, nor need to be raked up once the seeds have germinated.

PennMulch, used in smaller areas on campus, was invented in 1992 by George Hamilton, assistant professor of turfgrass science. Penn State has a patent on this substance, which is made from recycled paper and formed into pellets. When the pellets get wet, a green, gooey substance appears and that is what students may see on the ground.

Wood fiber mulch is sprayed on large areas that need to be re-seeded. Even though it lasts longer than PennMulch, the PennMulch is preferred here.

"It's a little more expensive per pound, but special equipment is not needed," Eckenroth said. A 60-pound bale of wood fiber mulch costs about $16, whereas a 50-pound bag of PennMulch costs about $12, he added.

Hamilton said PennMulch was "invented to have an easier way to apply and get the effects of wood fiber mulch."

Penn State landscapers generally do not use sod because the application is labor intensive, Eckenroth said.

Dining hall napkin compost, which is used in plant bedding, was never used to make PennMulch, Eckenroth said.

However, when the Penn State Newspaper Readership Program began, recycled campus newspaper was used to produce PennMulch, thus helping to "close the loop on recycling," Hamilton said. "In fact, some of the money that was saved went back into PSU's general scholarship program."

The newspapers are no longer donated to make PennMulch because of an increased demand for recycled paper elsewhere.

So if it's made out of recycled newspaper, why is it green?

Eckenroth said the material is dyed green to blend in with the surroundings and allow landscapers to see where they have applied mulch.

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