Alliy Gundlach cleans some tree seeds, preparing them for storage.

Gardening Green with Doug

Tree Pittsburgh and Seed Saving

Seed Technician Alliy Gundlach on seed collection,
easonal varieties, and the effects of weather patterns

By Doug Oster

November 14, 2024

It’s hard to believe the beauty which is hidden inside dried brown bulbs. Spectacular spring flowers are dormant, which need time underground during the winter to emerge with spectacular color in spring. When fall planted, they establish a good root system and can be added to the landscape until the ground is frozen solid, although sooner is better for planting. I always sneak the last planting in just as winter arrives in full.

Alliy Gundlach gently pushes small seeds through a deep green sieve, cleaning them and preparing them for storage at Tree Pittsburgh’s headquarters in Lawrenceville. The seed technician spends much of the season out in the field collecting seeds of trees which grow in our region, much of her time is spent searching for them in Allegheny County, but will expand her search into Ohio and south of the county too.

The seeds will be kept in a controlled environment, many will be sown and used in various tree projects for the organization. “Whenever I am collecting in the wild, she says, I'm trying to collect from the from the oldest trees possible. The largest ones I find in the forest.”

One of the goals for seed saving is genetic diversity, getting seeds from lots of trees and in different locations. “We want to have a nice mix just so we have the most resilient stock,” Gundlach adds.

Timing is everything when collecting seeds, she says. It often starts with the cottonwood trees, with their soft white bundles of seed in June, ramps up in the fall when many trees are producing seeds and goes into late winter for species like sycamore. She’ll scout some of her favorite areas in the spring to see how the trees are flowering, this gives her a good idea on where she’ll find the most seed.

“We have great partners all around the city, the Pittsburgh Parks, Hollow Oak, and Allegheny Land Trusts along with the county parks, says Gundlach. There are also cemeteries, different parks, state game lands, and other areas where she has permits to collect seed.

She relies on her experience to know when the seeds will be ready. “I mean it can be a two-week variation depending on weather patterns before or after when I expect something to be ready,” she says. There are many different conditions the seeds need to store and sprout. “It's so interesting because nature on one hand does its job and the forest regenerates itself in a way,” Gundlach relates. “But what we're always looking for is to have the highest germination rate possible, we do treat a lot of seeds differently and we will stratify them for different times and things like that.”

Stratification mimics nature with several different types of cold treatments to help the seeds germinate. There are many other ways the seeds are stored or planted, depending on the variety.

There’s a lot of science to saving, sprouting seeds and growing the trees out, but it’s also art, adds Gundlach. “A bit of what I mentioned before is the paying attention, the consistently watching, and then the art part is while you're cleaning seeds while you're processing,” she says. “What the textures are like, making notes of what things look like as you're working with them, and then in the spring as we watch how things grow, how that influences what happens in our seedlot, what's happening in our nursery stock.”

Every season brings with it new issues, this year the drought took its toll. “A lot of things were on average about two weeks early, she commented, a lot of the nuts were not filled, their embryos did not fully develop because their tree needs that resource just to stay alive rather than putting it into a seed.”

Most of the trees she collects from are natives, but some non-native cultivars that are not invasive and do well in urban environments will also add to the seed bank. Trees like dawn redwoods, Kousa dogwoods, and others.

When traveling across the area, she’s always keeping her eyes open for varieties that might be hard to find, but Gundlach has help too. “What's great is we also have a really solid volunteer base, she says, so they're always letting me know when they see stuff or even bringing in and donating seed, things like that.”

She’s always on the lookout for American plum, pin cherry, chinkapin oaks, as they are all hard to find in the region.

In the spring, Gundlach will begin planting the seeds, at Tree Pittsburgh they grow thousands of container shrubs and trees. “I never get over it, she says of watching the seeds germinate. It's so exciting in the spring and honestly, whenever it comes to the sowing, it's not that different than creating, you know, a growing schedule that you have at home.”

There are good years and bad years for different species, causing less than ideal germination or other issues. That’s one reason Tree Pittsburgh has a large seed bank. In good years they save lots of seeds to help during the off years. “If there's a natural disaster, anything like that, we're really well stocked to be able to help wherever we can,” she adds.

Gundlach has found ideal situation and gets joy out of what she accomplishes while working with the trees. “This job is perfect for me, it’s a blend of my passions, conservation and horticulture. Every year I get to look at the crop growing, knowing this is the future forest of Western Pennsylvania. Growing up here, it’s really meaningful conservation work. I also love the process of growing; I love being a horticulturist and nurturing plants.”

Here’s more information about Tree Pittsburgh programs, how to volunteer and help the organization.