ObjectFlow (for grasses, trees, animals) is a promoted feature in Orbx’s many airport 
products. Although it adds interesting stuffs to airport surroundings, it kills performance, too.
If you mostly fly your aircraft in the air rather than manuever it around airports, try cutting all or most of the ObjectFlow.dll in the DLL.XML file under the directory of fsx.CFG (C:\Users\<user name>\AppData\Roaming\Microsoft\FSX).
You could simply use the <!– –> notation pair for quick removal in case you want them back.
Try and see for yourself. You could be amazed.
FS Times 
Thanks Tom,
I believe people flow and nature flow are mostly impacting on FPS.
These can be disable using control panel.
Disabling object flow. dll may also stop season change color impact on grasses, trees and airport background.
Take care.
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Surely I know that comes with a price. It’s mentioned in the post but people could decide what they want at last.
Tom
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Top Tweak Tom Tsui!
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Glad to hear another positive feedback.
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Thanks for the tip. This is useful.
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Glad it helps.
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