I was looking through the XML files and discovered this:

    <ResourceType InternalName="R_PumpkingPatch_01">
        <DisplayName>Pumpkin Patch</DisplayName>
        <Description>This pumpkin patch can produce food by building a farm on it at 60% effectiveness.</Description>
        <LongDescription>
            It's rare to find a pumpkin patch out in the wild. Pumpkin patches tend to indicate that there was once a farm in this area.
        </LongDescription>
        <Type>FertileLand</Type>
        <PreferredTerrain>Land</PreferredTerrain>
        <HarvestType>Farming</HarvestType>
        <IconColor>0,0,0</IconColor>
        <Icon>Gfx//Icons//Res_Icon_Food.png</Icon>
        <ClothIcon>gfx\\TacticalIcons\\Res_FertileGround1.dds</ClothIcon>
        <TileDesign>R_Pumpkin_Patch_01</TileDesign>
        <ModelColor>0,0,0</ModelColor>
        <Production>1.0</Production>
        <PreferredTerrain>Land</PreferredTerrain>
        <NeedsToBeUnlocked>0</NeedsToBeUnlocked>
        <Worth>5</Worth>
        <Global>0</Global>
        <Rarity>100</Rarity>
        <Stored>0</Stored>
        <EnvironmentType>GrasslandEnvironment</EnvironmentType>
        <EnvironmentSpreadIntensity>100.0</EnvironmentSpreadIntensity>
        <EnvironmentSpreadRadius>1</EnvironmentSpreadRadius>
        <Medallions InternalName="FertileLand_Res_Medallions">
            <Default>Res_Fertile_Plains.png</Default>
            <Evil>Res_Fertile_Deadlands.png</Evil>
        </Medallions>
        <!-- AI Info -->
        <AIData AIPersonality="AI_General">
            <AITag>Food</AITag>
        </AIData>
        <OnSelectSFX>Click_FertileLand_01</OnSelectSFX>
    </ResourceType>

As you can see, the Production of the Pumpkin Patch is 1.0, while it should be 0.6.