The organiser of both events has said competitors should be prepared to pay higher entry fees as a contingency against cancellations and damage.
After 22 years, Scone Palace, near Perth, will no longer host the twice-yearly Central Scotland Horse Trials (CSHT).
And Balcarres International Horse Trials, which ran for the first time this year, will not continue.
Gillian Harrower of Scone said: “The recent wet summers have created challenging conditions for many outdoor events and their venues and Scone Palace has revised its strategy accordingly.”
And Lady Dalniel of Balcarres said: “We were totally undone by the weather and these conditions have had such an impact on the estate that it is with deep regret we have had to take this decision.”
James Oakden organises both events. “Winter and spring were spectacularly wet, then we had the worst weather possible for Balcarres,” he said.
“We did not get the gate we had hoped for and [the event] caused a terrible amount of damage to the park, which was very expensive to fix.
“The estate wanted a guarantee from us that it would not happen again and we could not provide that.”
The CSHT committee is working with British Eventing (BE) to find a new venue.
But Balcarres will not find a new home, unless an existing event can take it on.
“I am not setting up an event on a greenfield site again,” Mr Oakden said. “It all boils down to liability.”
He said eventers should pay more to take part, so events have money for the years when they make a loss.
He suggests grass-roots competitors should pay a £100 entry fee with a £20 start fee, and novice riders £150 and £25.
But BE does not want riders’ costs to rise.
Chief executive Mike Etherington-Smith said: “BE works tirelessly to keep costs down for members, organisers and owners.”
The loss of Scone is also a blow to the Fife Hunt branch of the Pony Club, which tagged its one-day event on to the April horse trials.
District commissioner Marian Lamb said: “It’s a huge disappointment.
“There are very few Pony Club one-day events in Scotland and ours was a major fundraiser for the branch.”
This news story was first published in the current issue of H&H (4 October 2012)