It is not advisable to apply fresh farmyard manure because
Answer Details
Fresh farmyard manure is not advisable to apply directly to crops because its heat of decomposition can be too high, which may lead to scorching or burning of the plants. Additionally, it may contain harmful microorganisms that could be detrimental to the plants. It is also possible for fresh manure to increase soil acidity, which could be harmful to plants that prefer neutral or alkaline soil pH. On the other hand, fresh manure does not usually increase soil alkalinity, as it generally contains more acid-forming compounds than alkaline-forming compounds.