Grappling with #7 PLA

Grappling with the infamous #7 PLA recycling code

What was the plastics industry thinking when it stuck compostable plastic into this recycling hodgepodge?

It wasn’t … thinking of recycling, that is. The industry says their category numbers are resin codes, not recycling codes. They identify different types of polymers. Each polymer recycles using a different method or technology. And #7 PLA is no exception.

A few years back, modifications made the symbols a little less recycling-forward. Recycling’s ubiquitous “chasing arrows” triangle that once outlined each number changed. It’s now a solid line to further distinguish the codes from recycling symbols.

Motivation for the mod? All resins do not recycle in all communities. The standards lords wanted to make sure everyone understood this simple truth.

2019 certified compostable logoBut people use them for recycling. That makes them – albeit ipso facto – recycling symbols.

The Biodegradable Products Institute (BPI) and U.S. Composting Council (USCC) work to dispel the confusion. They promote a unique symbol for compostables. This logo indicates a product, container, or packaging certified compostable by the BPI.

Know all RIC Codes, not just #7 PLA

Resin Indicator Codes (RICs) 1 through 6 identify specific plastic types. Everything else gets lumped together in the plastics proxy for the kitchen junk drawer — RIC #7/Other. When compostable resins joined the family, they landed in the junk drawer, too.

Code 7 compostable — a.k.a. #7/PLA — indicates a plant-based resin that will degrade under certain conditions. Unfortunately, a landfill isn’t one of them, though that’s where most of them end up. They’re not very “biodegradable” in the wild, either.

In truth, few communities recycle any Code 7 plastics.  Code 7 compostables require processing at a modern, high-rate composting facility. But there just aren’t that many around.  Even a #7/PLA composter might require in-house degradation testing if the plastic is not BPI-certified.

Compounding the problem, Code 7s are showing up in recycling streams for Nos. 1-6. In these bins, a Code 7 plastic represents a contaminant. One misplaced container can destroy an entire recycling batch if not removed. No. 7 /O (Other) will also contaminate an otherwise compostable No. 7/PLA stream.

Bottom line: pay attention to those RIC codes. Don’t assume any plastic is recyclable. Determine which resins the community does recycle, first. This is true for No. 7/Other and No. 7/PLA, too.  If not on the local “accepted” list, make sure the resin doesn’t wind up in a recycle or compostables bin. Better yet, choose a product that can recycle where you live.

YOU MIGHT ALSO LIKE AN EARLIER POST:  “Is biodegradable plastic compostable plastic?”

Noel Lyons


Sean Fallon


Gary Gittere


Kate Sullivan


Members of Team McGill are packing up for next week’s 2018 Carolinas Recycling Association (CRA) Conference, March 19-22 in Cherokee, NC.  Representing McGill Environmental Systems will be Noel Lyons, president; Sean Fallon, business development manager for intake;  Gary Gittere, sales and marketing manager for compost sales, and Kate Sullivan, compost sales rep.  Come meet some of the folks known as The Compost People®.  Flag ’em down in the hall, tag someone after a session or simply visit the McGill booth and say “Howdy!”

Transplanting can be a tricky business.  Whether moving from a greenhouse or a personal garden, plants do not care for the experience.  And transplanting can sometimes trigger a disastrous response from the plant.

When the stress or damage is too much for the plant, transplant shock may result.  The plant either wins the struggle to adapt to its new home or dies. Different species and varieties of plants can handle transplanting better than others, but the threat is always present.

Usually, transplant shock can be caused by a failure to allow the plant enough time to acclimate to a new temperature. This is especially true if the plant has been raised in a protected condition such as a greenhouse. Another cause is when the roots of the plant have disturbed too much during transplant. Other factors that can make a difference include the weather conditions during the process, and the treatment the plant receives shortly after transplant.

Compost is an effective way to combat transplant shock, as the mechanisms of compost work well to help make the process go smoothly. Unlike fertilizers, compost requires fewer applications and will last longer keeping the soil healthy. The additional nutrients will also help the plant acclimate to its new home and lower stress levels. Reducing the amount of stress a plant experiences is paramount to a good transplant.

Immature/unstable composts can increase difficulties for transplants, so be sure to choose a quality, stable compost product like McGill SoilBuilder, especially if planting under plastic.

Amending soil with compost builds soil organic matter (SOM) and replenishes soil microbial populations.  Both help all types of plants –from vegetables to trees — to not only survive the “shocking” indignities of transplanting, but thrive throughout the season.

Read more about transplant shock and compost: