Trees grown in an ideal location would have no need for pruning as they prune themselves over time. i.e. dead limbs and broken branches. But as we humans like to plant trees in our urban environment, sometimes in small areas, trees can quickly outgrow their surroundings. There are many different forms of pruning, from crown reductions, lifting, thinning and more. Each tree and each environment is different so careful consideration should be taken to ensure your tree’s health and your needs are in best interest. Many companies offer pruning services or topping services etc but have little knowledge or expertise in the industry. Often work carried out by these people can lead to more problems in the future so make sure whoever it is you choose has the correct solution.