New to standardbred horseracing? Learn about Ontario Sire Stakes!

Who is Ontario Sire Stakes (OSS)?

Established in 1974, it is a program dedicated to promoting the breeding of Standardbred horses in Ontario. They provide economic incentives to breeders to ensure high-quality Ontario Sired horses (a sire is the horse’s father). OSS has helped expand the knowledge around the world of the large Standardbred industry we have right here in Ontario. Grand River Raceway is also proud to acknowledge the high-quality drivers, trainers, owners, and caretakers that live in and around Wellington County!

To be eligible to the program the stallion (the uncastrated male horse) must be owned or leased by an Ontario resident. They also must have been in the province for his entire breeding season. If a stallion is a “Dual Hemisphere stallion” it must remain in the province of Ontario for 170 consecutive days. Only foals (young horse) resulting from a mating between a mare in the Northern Hemisphere and a stallion registered for the OSS program are eligible for nomination to the Ontario Sires Stakes.


How can an Ontario standardbred horse race in the OSS program?

The OSS program consists of series races for two-year-old and three-year-old trotters and pacers. These races are held at tracks across Ontario from May to November every year. This program also highlights the great breeders, trainers, and drivers that live right here in Ontario. Providing them a large platform to showcase what they do best.

There are two programs consisting of two-tiers of racing – Grassroots Series and a Gold Series. In the Grassroots Series there are five legs, a Grassroots Semi-Final and Grassroots Championship race for each category of age, sex, and gait. The Gold Series consists of five legs, followed by a Super Final at the end of the season for each category of age, sex and gait. Horses can only be registered for ONE of each series.

Horses must race in the Prospects Series prior to entering the Grassroots or Gold Series programs.


What are local Centre Wellington drivers and trainers saying about OSS?

We have several OSS local heroes right here in Centre Wellington. Calling Arthur, Ontario home, Trevor and Shannon Henry are partners in life and in business.  They have had long-standing hugely successful careers in the Standardbred industry, and their shared commitment to the industry (and each other) makes for a solid foundation of teamwork. Trevor is a decorated driver with $71 Million and counting purse earnings, over 7,200 career driving wins, three-time Lampman Cup Winner for top Ontario Sire Stakes driver, and so many more accolades! Trevor gives a lot of credit for his success as Shannon has an extensive and successful career in managing and training the horses they own. She knows the business and takes care of coordinating his driving schedule and calls in his changes while he’s on the road. They are proud to be part of the OSS program as two well-known influences in the local (and Ontario) Standardbred industry.

“Ontario Sires Stakes is some of the best racing around,” says Trevor Henry, Driver. “The program for Ontario Sired horses only keeps your money in Ontario and the purses are some of the best in harness racing. The program showcases the rich history of harness racing in Ontario. It has three levels you can compete at and collecting the points throughout the summer makes for exciting racing! Having come from a family that has been involved with the Ontario Sires Stakes since it first started in 1974, I can tell you that you will not find a better program than this one to race your horse.”

“Ontario Sires Stakes is a very big part of our fall yearling purchases,” says Shannon Henry, Trainer. “The program is well laid out and the thrill of watching some of the best drivers and horses compete is exciting! It is some of the best money in harness racing. Having Ontario Sired horses allows you to be front and center with your horse as the circuit is manageable enough to travel between races. There is no better program than the Ontario Sires Stakes.”


Get the full OSS schedule here:

Get a PDF of the GRR OSS Racing Schedule


How is the program funded?

This is a more complicated part of the OSS for beginners but overall, a portion of the Ontario wagering is reinvested into this program to ensure it is a continued success.



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