Cone Collection for the NC Forest Service

In recent years the NC Forest Service has been growing hemlocks from seed in great numbers in order to establish protocols for future production of hemlock strains that can be used for large scale forest restoration. This requires that they collect thousands of cones each year, and they can use your help!

There are a few ways for you to get involved:

1. You can collect cones independently from your own trees (or your neighbors’ trees if you have permission).
2. If you have a number of trees with lots of cones (a minimum of 1 gallon/4 pounds of cones) on your property, but are not able to collect them yourself, NCFS County Rangers or HRI staff/volunteers may be able to assist you with collecting.
3. You can volunteer to help us collect cones from identified areas.

If you have cones that you can collect yourself or have a good site where the NC Forest Service can come collect, there are a few key points to keep in mind.

• Tree selection. The trees can be eastern or Carolina, yard or forest, treated or untreated. Just be sure they are one of those two hemlock species. If you have both species producing cones, the collections will need to be kept separate and labeled appropriately. (See additional information on species identification below.)
• Permission and accessibility. If collecting cones yourself, make sure they are on your property or that you have permission from the landowner.  If it is a suitable location for the NCFS or HRI to collect, again it should be from trees where we have permission or could obtain permission to collect. The cones should be reachable from the ground, with ladders or using a bucket lift on a truck. Hedges are ideal if they have cones because they are easier to collect from the ground. In order to use a lift, the trees need to be in areas that are relatively flat and accessible to a truck. Even if we aren’t able to collect from them this year, it is helpful to the NCFS to know about locations for potential future collections.
• Time of collection is important.  Cones should be ripe but still retaining the seeds. Please note: Hemlock will retain brown cones from the year before on the tree and some of these may have seed in them. These seeds will not be viable. Only this year’s cones are of interest. (See additional information on ripeness and collection below.)

Please review the detailed instructions below on cone collection.

Eastern vs Carolina hemlock identification

When collecting it’s important to keep eastern and Carolina cones separate and label them with the correct species.

Eastern hemlock (Tsuga canadensis) is by far the more common species and grows across a much wider range. Carolina hemlock (Tsuga caroliniana) is much less common and found naturally on drier, rock outcrops and ridges; however, it may occur as a planted tree in a variety of landscapes. 

Identification characteristics include:  

• Eastern needles tend to come out of the twig in one plane, more or less in a line on both sides of the twig. 
• Carolina needles are whorled around the twig (come out in all/most directions) and are longer on average than eastern needles. 
• Eastern hemlocks, especially in the sun, can fan their foliage a little, but it will still be roughly just coming from the sides of the twig. 
• One difference that takes a little discerning is that most twigs on eastern hemlocks will have a line of “upside-down” needles along the top side of the twig. These needles show the white stripes, which are usually on the underside of the needles, on the top side instead.
• Cone size is much larger on Carolina hemlocks than eastern.  Eastern cones are around ¾ inch while Carolina cones are up to 1.5 inches. 
• This guide may help you with identification

Timing and hemlock cone ripeness

As new cones ripen, they will turn from bright green to yellowish green and then progress to a purplish brown color. The closer to the purplish brown color they are, the better (as long as the cones are not beginning to open). Ideally the cones should be closed when collected. The seed in the cones will continue forming until full maturity and germination improves the closer you get to full ripening. 

As previously mentioned, cones that appear with a purple hue (#4-6 in the photo) are ideal. The closer to maturity they are, the better the actual seed yield. If they are too green the seeds won’t be fully developed. If the cones are fully open, the seed may have already dropped.  

Realistically, collecting when most cones are somewhere in the middle of that sequence of ripening and being able to get them before the seeds drop are the important considerations.  Cones scales in the later stages can open and close based on relative humidity. If the scales have opened it is likely the seeds have dropped already. Therefore, if you collect cones in the later stages, please check a few to see if seeds are still present. You can cut a few cones in half longitudinally to look for seeds.

You can see in that picture that there are only a few viable seeds in the cone.  It takes a lot of cones to get a little seed.  Some might ask why this is so – not every cone scale contains usable seed.  All of our collections are wild collections so seed bugs and other factors keep seed per cone yields down.  Also, some scales do not have a viable seed due to the cone development following pollination. 

Collection

Please label each collection with the following:

• the hemlock species (eastern or Carolina)
• the date collected
• the county the cones were collected from
• the name and contact info for who collected them
• the number of hours volunteers spent collecting and transporting the cones

Place the label inside the bag with the cones. You can print this form or use it as a guide.

Collected cones should be kept in burlap, cloth, or paper bags, and separated by species. Cones should be stored in a cool, dry place, like a cool basement or air conditioned room, or can be kept in the refrigerator until they can be dropped off, but make sure the cones are stored dry.

We have encountered some mold appearing on cones in the past. Storing cones one layer thick to allow for air flow (on cardboard or a paper-lined baking sheet) may be helpful in preventing mold, as well as storing cones in multiple bags with less cones per bag. Collecting cones on dry days, or in sunny, dry conditions will also prevent mold problems. We thank you for taking these precautions.

Drop off

Cones can be dropped off at your local NCFS county ranger office, but please call ahead to arrange a drop off time. Cones can also be dropped off at the HRI office in Asheville or the NCFS Linville River Nursery near Crossnore. Please make arrangements with us to drop at either of those locations by contacting us at volunteer@savehemlocksnc.org or 828-252-4783.

Please let HRI know what you did. If you are dropping off your cones directly to the NCFS (county ranger or nursery), please send the information on your label to us as well. Click here to print the label. You can send us a scan or photo of the completed paper copy or type up the info in an email to volunteer@savehemlocksnc.org or fill out this Google Form. This information is used for our volunteer reporting, which helps us with current and future grants.

Message from Jim Slye, NCFS Nursery and Tree Improvement Program Head:

Last year’s collaborative collection effort was a huge success. Altogether, we collected 417 lbs of eastern hemlock and 8 lbs of Carolina hemlock. The “Silver Hemlock Award” went to Macon County for 105 lbs of cones and NCFS District 1 out of Asheville for 298 lbs of cones collected (6 of the 8 counties in that district collected cones). We also had good collections from Stokes County, Guilford County, and Lincoln County, totaling 10 different counties in which cones were collected. We enter this season with hopeful anticipation, looking forward to seeing which counties/districts bring in the most cones this year.

In addition to the “Silver Hemlock Award,” this year HRI will announce which county had the highest level of volunteer participation!

We’d love to receive action shots of you collecting cones or standing in front of your trees showing off your haul! Please email photos to volunteer@savehelmocksnc.org. See some highlights from previous years below.