Which statement about irrigation systems is NOT one of the three main types used in commercial horticulture?

• A. Overhead sprinkler/micro-sprinkler systems are one of the main types
• B. Drip irrigation is one of the main types
• C. Subirrigation is one of the main types
• D. Fogging irrigation is not used as a main type

Answer: (D)

In commercial horticulture, the primary ways water is delivered to plants fall into three main methods: overhead systems that spray water from above (like sprinklers and micro-sprinklers), drip irrigation which applies water directly to the root zone through emitters, and subirrigation which delivers water from below the root zone, often through benches or flooded beds. Fogging is not considered one of these main delivery methods because it is mainly used for humidity and microclimate control rather than as a primary way to supply water to the plants’ root zones. It creates a fine mist to adjust air moisture or temperature, but it doesn’t provide the consistent, targeted irrigation that the three main types are designed to achieve. So the statement about fogging not being used as a main type identifies a method outside the standard trio, making it the correct answer in this context.