Fifteen fire engines and 97 firefighters and officers dealt with a grass fire on Staines Road in Feltham.
Grass land the size of five football pitches was damaged by fire.
Smoke from the fire has travelled near to Heathrow airport but it did not affect their operations.
Fourteen horses were removed from a nearby field to a place of safety.
The number of resources were there to help with water relay.
A London Fire Brigade spokesperson said: "During the hot weather we are attending a large number of grass fires across London.
"We’re asking the public to take care not to drop cigarettes or matches on dry grass and to keep a very close eye on barbecues.
"Dropped glass can also start fires as the sun can magnify the sun’s rays.
"Grass fires can quickly spread and cause serious damage, so if you see grass smouldering, please call 999 immediately.”
• Never leave camp fires or barbecues unattended and extinguish them properly after you have finished using them
• Clear away bottles, glasses and any broken glass to avoid them magnifying the sun and starting a fire
• Dispose of smoking materials such as cigarettes safely
• Explain to children the dangers of playing with and lighting fires
The Brigade was called at 1559 and the fire was under control by 2143. Firefighters from Feltham and surrounding stations were at the scene.