Which of the following is NOT a type of trimming technique?

The technique referred to as cross trimming does not exist among established trimming methods. Trimming techniques are generally categorized based on their orientation and the specific effects they produce. Through trimming typically involves cutting along the grain or the overall length, under trimming focuses on cutting material from below or underneath a section, and topping entails cutting off the top growth of a plant or structure for a desired shape or height.

The absence of cross trimming from recognized practices indicates that it does not fit within the conventional framework of trimming techniques. This understanding is critical for anyone studying the practices involved in trimming, as it helps differentiate between valid methods and those that are not formally recognized.