Dispatches from the Living Artifacts

*Title of this newsletter subject to change

“From the finest and bestoaks wise persons will secure acorns for planting” – Walter Scott - 1976

9/12/2023, by Matt Noone with editing help from friends and fellow tree growers

On the afternoon of August 20, 2022, the car was loaded up with wagons, empty garbage cans, tarps, 5-gallon buckets, and most importantly the Bag-A-Nut machine. We headed out to the Yahara Hills Golf Course, where a golf cart was waiting, ready to assist us with our acorn collection.

My 4-year-old son and I had been searching for Heritage Oak trees for the previous several months, always looking for trees, sometimes with binoculars, that would have a bumper crop of acorns in the fall – only to be disappointed time and time again. In fact, we were barely able to find any oak trees with acorns in Dane County.

But at last, we found our first Heritage bur oak grove with a remarkable acorn crop. In just one trip we were able to collect 50 gallons of Heritage acorns from several trees. These acorns will eventually make their way to a nursery and then on to new permanent homes, where they will enhance the tree canopy and continue their native tree lineage, all as part of the larger Dane County Heritage Oak Project.

In 2022, the Dane County Heritage Oak Project set out to inventory the roughly 250 remaining Heritage Oaks originally catalogued in 1976 by Walter Scott.[1] The trees identified in the original inventory were later re-inventoried by Bruce Allison in 2001, this time with GPS coordinates. In 2022, the Dane County Heritage Oak Project continued this unique inventory that began nearly 50 years ago.

The initial purpose of the current inventory was to document how many of these living artifacts, trees present on the landscape prior to our country’s founding, were still standing today, continuously providing shade, ecosystem services and inspiration to generations of humans. While a noble endeavor in and of itself, the project has since produced some interesting offshoots.

One of those side projects grew out of conversations with DNR Urban Forestry staff regarding the need to collect seed from trees of natural origin for the state’s reforestation program. “Natural origin” refers to wild seed not originating from landscaping trees or trees from private nurseries. It quickly became apparent that trees identified through the Dane County Heritage Oak Project were exactly the type of seed source that DNR nurseries were seeking.

Collecting seed from the identified Heritage Trees proved to be more difficult than one may assume. While we anticipated a race to collect acorns before the hungry squirrels, chipmunks, raccoons, and crows consumed them, the real challenge turned out to be locating trees with a significant acorn mast. Depending on the species of oak, a significant mast occurs on a cyclical basis every 2-6 years. Additional factors impacting mast years include weather conditions, drought conditions, and other related stressors.

For species in the red family (red oak, black oak, northern pin oak), acorns take two years for development, as opposed to species of oak in the white oak family (white oak, swamp white oak, bur oak) that develop in one year. This development difference further compounds factors that affect the likelihood of a successful mast crop for red oak family members.    

In fall 2022, Yahara Hills Golf Course was the only location in all of Dane County where we were able to identify a significant acorn mast from Heritage bur oaks.[2] A second significant mast was found from a heritage red oak grove at Hudson Park (red oaks drop their acorns typically 1-5 weeks after the bur oaks). The City of Madison Parks Division allowed and assisted with acorn collection at these public locations. Between the end of August and middle of September, we collected well over 100 gallons of acorns at these two sites from just six trees.

The Dane Country Tree Board is currently growing about 200 of these trees, with plans to expand collection efforts and growing capacity in 2023-24. However, the Dane County Tree Board’s growing operation success is dwarfed by that of the experienced experts at the DNR’s Wilson State Nursery in Boscobel, where the majority of the Heritage acorns were sent. Currently there are over 10,000 Heritage bur and 10,000 Heritage red oak heritage seedlings successfully growing in state nursery fields.

Significant potential white oak masts have been identified for collection this fall; we are still looking for Heritage swamp white oak for collection. Conversations and plans are currently ongoing on how to most impactfully use these trees for reforestation efforts and educational opportunities, all while preserving time tested, resilient, native tree genetics.

To learn more about collecting seed for the DNR, contact your nearest state nursery. To add Heritage trees to the inventory, contact Matt Noone at [email protected]


[1] For more information on the original inventory, see Our Oldest Oaks – A Living Heritage

[2] Bur oak acorns differ in size based on their location and latitude; acorns produced in northern locations are much smaller than acorns produced from southern populations. Interestingly, the acorns collected from the bur oaks at Yahara Hills Golf Course were very small and resembled acorns from much more northern populations rather than what is typical for our latitude.

Seed collection from a Heritage bur oak at Yahara Hills Golf Course in Madison, the only location of an observed Heritage bur oak mast in 2022.  

Bag-A-Nut machine, a specialized acorn collector, lent to CARPC and Dane County Tree Board to collect Heritage Tree acorns from the WI DNR. Operates similarly to a golf ball collector at a driving range.

The season to collect acorns is short. Collectors must be ready to collect at all times – or at the drop of an acorn, starting mid-August.

­­­Bur oak acorns collected from one afternoon’s work. 

Bag-A-Nut machine in action collecting red oak acorns. Bur oak acorns retain their caps after they drop.

Heritage red oaks leafing out. These acorns were planted in the fall. Other acorns were placed in cold storage.

Dane County Extension bur oaks, photo taken in late July 2023.

Over 10,000 Heritage red oak seedlings growing at the DNR’s Wilson State Nursery in Boscobel. Middle row are the red oaks, towards the back of the row – a change in color and texture - the bur oaks can be seen. 

Over 10,000 Heritage bur oaks seedlings (middle row) growing at Wilson State Nursery. 

Heritage red oak growth (shoe size 11). Photo taken June 7, 2023.

Heritage bur oak growth. Life expectancy for species in the white oak family can exceed 300 years, white oak species typically have a slower growth rate compared to red oak species. Photo taken June 7, 2023.

A single chipmunk will rip out numerous oak seedlings in a single day given the chance. Just because your oak seedling is now over a foot tall does not mean it’s safe from predation. 

In the urban environment removing rodents is a waste of time and will not result in protecting your trees. It turns out there are unlimited rodents in the city.

Rodent proof ½ inch hardwire cloth cage. Next cage I build I will use ¼ inch hardwire cloth.

2023 Fall Collection, the cycle continues, repeat the process but this time - with lessons learned. Collecting acorns from Schenk Elementary School August 23, 2023. No Bag-A-Nut machine required here, just a broom and a snow shovel. These acorns are all coming from a single tree with an exemplary mast – when collecting, this is what you look for.