Tree shelters affect shoot and root system growth and structure in Quercus robur during regeneration establishment

Tree shelters are used in many forestry applications because they often improve survival, may stimulate early growth, and can help to maintain apical dominance. Quercus robur, widely used in multipurpose plantings in Europe, usually grows slowly and loses apical dominance in the early stages after establishment. We examined tree shelter effects on Q. robur seedling field establishment in Italy, focusing on the influence on shoot system structure (branching, apical dominance), root system development, and shoot versus root system balance. We conclude that shelters modify the above- and below-ground structure and balance of regenerating oak seedlings in the early field stages, promoting development of productive plantations that may require reduced cultural intensity. However, above-ground growth was not equally balanced by below-ground development, which may lead to disadvantages especially under harsh site conditions.