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Last year, we moved our native plant nursery forward by introducing our mixed provenances and assisted migration program. Now it is time to let it settle with the public and the plant industry.

This year, we want to move our honey based farm forward. We will be taking some conventional agricultural methods and using them in an unconventional way – to farm for pollinators. As we restore the land from marginal status growing invasives to pollinator friendly, we will blog and post articles on the science behind it all.

These articles will provide information that can be used no matter what the scale, from agricultural sized tracts to the backyard. We are hoping that by blogging of our experiences and lessons learned we might encourage all people to try a similar journey.

Really looking forward to spring!


Why do people want pawpaw? The answer is simple, uniqueness. In every aspect, pawpaws are unique and are like a crown jewel in anyone’s garden collection. Even the name, Asimina triloba, sets the plant aside. Asimina translates to ‘ food of the gods ‘ and refers to the strange mango looking fruit produced. Triloba refers to the strange three lobed flower.

This tree was a hugely popular tree for the native inhabitants of North America and when the Spanish started to explore the Mississippi valley, back in 1541, the Conquistadors named the fruit ‘ pawpaw ‘ after the Spanish word papaya. This tree, native to North America, produces the largest edible fruit. It was the major source of fruit for the native American since the present day apple was brought from Britain in 1625. Hard to believe the cultivated apple tree is not native.

In the wild, these trees grow in thickets in the forest understory and along woodland edges. They prefer fertile soil that is well drained. The amount of sunlight will determine the shape of the tree where dense growth is typical of sunny conditions and a more open growth is indicative of shady conditions. They have moderate growth rates and will attain heights of 15 – 20 feet and widths of 15 – 20 feet.

Unfortunately, people stopped seeking out pawpaw in the forest when apple tree cultivation became popular. At the same time, massive deforestation for land colonization happened which vastly decreased populations and left only scattered remnants of pawpaw. Finally, this tree is coming back to popularity. There is renewed interest since there is potential for organic insecticides from its ground up bark and leaves. Also, extracts from pawpaw can overcome the ability of some cancer cells to reject chemotherapy.

You would assume, with this renewed public interest in this tree that propagation and growth of pawpaw would be embraced by the horticultural industry. – Nope.  To see the full story please follow the link.

But no matter what the difficulties, be sure to plant these trees. Once established, they are self sufficient. They are generally pest free, drought resistant and will multiply by suckering to create a lovely thicket. Even though pawpaws look exotic and have beautiful flowers, I planted them for the butterflies. The pawpaw is the only larval plant for the zebra swallowtail butterfly. Since there are few pawpaw we now have few zebra swallowtail butterflies.

Whatever your reasons, be sure to plant the lovely and unique pawpaw.


It is never just about finding ancient trees and collecting seed to preserve their genetics for generations to come.  There is so much more – the human connection.  Inevitably, when you find the ancient tree, there is a human guardian connected to it.

So is the case of the St Cuthberts white oak.  The Lea family, back in 1818, was one of the founding families for the Leaside area.  By 1890, the Lea’s donated land for construction of a church.  There was no steeple built.  The white oak that was present during construction acted as the focal point of the church.  Today, to find the church just look to the sky and the giant white oak guides the way.

We were honored to meet the church representatives and tree enthusiasts last week on our quest to find this tree.  Thanks to the tree guardians, this tree has received Heritage status and still graces the side of the church.  Unfortunately, this great white oak is just a remnant of the old growth forest that once covered this terrain.

We are hoping that next year will not be a drought year and we will be back visiting the St Cuthberts white oak on a quest to retrieve acorns.



Height 213 m

Circumference 518 cm

Age approximately 400 years old



This 400 year old tree in Niagara is the official boundary marker in the first land deed in Upper Canada signed in 1781 between the Chippawas and the Mississauga and the English Crown. The deed, signed by King George, was for a 4 mile wide strip of land bounded by the Niagara River between Lakes Ontario and Erie. To mark the boundary, the 4 First Nations chiefs chose a large, white oak, forked 5 feet from the ground near Lake Ontario at a distance of 4 miles from the west bank of the Niagara River.



This is a designated Ontario heritage tree.



We were very happy to track down the location of this magnificent tree with the help of Forests Ontario.  The 2 men responsible for getting this tree designated as an Ontario heritage tree are seen in this photo.  Unexpectedly, it turned out to be a mast year for this old tree and we managed to collected 200 germinated acorns.

This trees’ legacy will live on!




We have been very busy scoping out the Lake Erie shoreline looking for southern seed sources.  With the launching of our assisted tree migration program we needed southern seed sources to bring northward so that we might be able to offer mixed  provenances.

We have been blessed this year to see many new places in Ontario as we go exploring.  What a great job.  I really can’t consider this work when we get to travel to so many beautiful and fascinating places and meet great people.


I think the only red oaks that produced any meaningful amounts of acorns was at Crystal beach.   Wow – these oaks were already present when the lake shore cabins were built around 1904.  What an incredible view as these red oaks arch over the roadway and extend to Lake Erie.  So glad work took us there!




This weekend we went on a historic walk.  We went to the historic village of Swansea which is more than 300 years old.  This village was completely surrounded by the city of Toronto, and by 1967, had been amalgamated.

As far back as 1615, indigenous peoples and settlers have been using this area for travel.  Etienne Brule, walked the Toronto Carrying Trail and stayed at the native encampments at the Humber River.  By 1793, this area was declared a mill reserve so that the forests could remain intact for the use of the King’s sawmills.  This area was unused and eventually was turned into parks and house lots.

It was this rich historic area that we explored in hopes of finding some of the ancient white, red and black oaks.  It took a bit of sleuthing since it is old residential area with many of these ancient trees residing in backyards and private property.

So much fun – we will be back to investigate again!


So many people ask what is the best to plant for pollinators to feast upon.  I base my recommendations on published bee appeal values posted by universities.  I only selected plants that rated very good or excellent for bee appeal.  Also, we only selected native species since these species have developed special bonds with our pollinators.

Here is the listing.







Canada and American Plum


Ohio Buckeye

Eastern Redbud

Northern Catalpa



Indigo bush





Eastern flowering dogwood




Honey locust




We have done a great deal of research to try and get the principles of assisted migration correct. Luckily, we were able to contact some of the authors of the research papers we used. Generally, they all agreed we had the right data. Some were glad to see their research being implemented and some were much more cautious.

We wanted input from the MNRF about our program. In a nut shell, the MNRF is focusing on updating the seed zones and in the future they may be able to deal more directly with assisted migration.

For us, Phase 1, has been to get articles and information available and getting a conversation going. We need to have all industry and government talking. And we need to keep talking. This is not an easily resolved issue nor is it a static program. As climate changes we must reevaluate our targets and watch how our transplanted forests respond.

We will be starting Phase II, this spring, where we will vastly expand our seed collection sites. We need to start growing more southerly originated stock in order to start blending provenances.

We have also created genetic maps for our clients to keep track of seed sources used. In every planting we want to create the broadest genetic base possible. Irregardless of assisted migration, the key to any resilient forest or small planting is genetic diversity.

We will gladly dialogue with all interested parties and government and update our program accordingly.

This is just the beginning…we are going to have so much fun!



In Ontario, there are 35 static seed zones. These were established to ensure that planting stock was climatically adapted to the region of planting. This supported the approach of ‘ local is best ‘ where locally adapted seeds would be more acclimatized to the site. Recommended distances were no more than 50 kilometers from the parent stand and, if possible, less than 30 kilometers.

What is strikingly clear is that static provenances are no longer valid with a changing climate. Climatic envelopes, areas of suitable climatic habitat for tree species, are shifting north. This change will be ongoing and unrelenting. It is this unrelenting change that has us paralyzed.

So what are some issues concerning assisted migration? It is the intent of assisted migration to push seed provenances north or even introduce new species north and accomplish climatic adaptation in 1 generation in what would have taken nature several generations to achieve. One of the biggest risks of planting stock north of its current zone, is freezing damage. Natural selection has resulted in species aligning their growing cycles to avoid damage from late spring and early fall frosts. Events such as breaking dormancy, bud burst and flowering are carefully timed for tree species adapted to a local environment.

On an even larger scale, we could be mismatching tree species to photo period. By moving seed sources north, species are no longer matched to local day length. Longer photo periods experienced at more northerly latitudes may cause trees to be more susceptible to all frosts. By mid century, it is estimated that most of Ontario’s tree species will have to move 400 to 600 kilometers north to keep withing their climatic envelopes. This will, indeed, cause mismatching of tree species to photo period.

We have decided, at Puslinch Naturally Native Trees nursery, to take the plunge. We will be launching an assisted migration program. A huge undertaking but we have always been committed to a sustainable environment and forests. Now the hard work begins where we build the program and try to introduce it to our clients and general public.



People usually do not think of trees being able to migrate. But this is untrue. If you just think back 12,000 years ago, trees migrated just ahead of the crushing forces of advancing glaciers in Canada. Trees would sexually mature, send out seed and pollen ahead of the glaciers and create an advancing line of trees, moving southward. As a matter of fact, DNA testing found that some white pine tested in the Mississippi valley had come from the Algonquin park area. Of course, migrating birds and wildlife help move seeds of trees by ingesting seeds and later fertilizing another area with droppings. The native people of various regions would plant favored shrubs and trees, such as yellow wood, on their travels. In this way, they were always assured of having this plant material available.

So what I have just described is the process of migration for plants and trees. You can imagine my level of confusion when I happened upon the new term, ‘ assisted migration ‘. So were they just renaming an old term? Turns out, No. To truly understand this terminology you must believe in climate change and its consequences.

Through industrial activity and tropical deforestation, we have set the planet on a course to warm to temperatures not seen in the past 100,000 years. Earth has seen similar warmings in the distant past but the RATE of these warmings were at a substantially slower rate. For Ontario, warming is projected to be greater in the North than the South.  Precipitation wise, Northwestern Ontario and most of Southern Ontario will see a 10% decline along with an accompanying increase in temperatures. By 2100, we should see our annual temperatures rise by 6C. Overall, at a forest level, soils are going to be drier.

So what has been the immediate impact on our forests and tree species? Basically, as the climate changes, some individual trees or even whole local populations of a species may not prove adaptable to the new conditions, nor have the capacity or time to become adapted. These trees may not be able to migrate to more favorable conditions, given that climate is changing faster than natural migration via wind, water and animals, has occurred in the past. Another negative effect, a barrier to migration, is temperature and other weather extremes affecting flowering and seed production.

When you hard boil all the scientific evidence down, the real problem is the tree migration rate needed. Historically, trees can migrate at less than 10 kilometers per 100 years. With climate change and warming happening even faster than predicted, trees will have to move 150 – 200 kilometers in the next 100 years to ensure continuation of tree species within favorable climatic conditions. Obviously, the evolutionary migration rate of trees cannot keep pace with the anticipated rates.

What to do? The choice seems to be assisted migration. It is the intentional migration or relocation of southern trees species north, by man. It is a planned relocation of species, still within its natural growth range, but at the northern extent of its current habitat. In my next article, we will look at the mechanics and controversy of assisted migration of trees.