Norma Granada. Assessment

When you walk through a park or garden, you do not even consider that that resource of the city through which you are walking may have a specific value, sometimes even quite high. Well, it does, but do we know how much it is? Do we know how to calculate it? Today at Gardenprue we explain how the Granada Standard works .



Since 1990, the Spanish Association of Public Parks and Gardens (AEPJP) has developed the Granada Standard, a protocol to follow for the valuation of parks and gardens, the product of many years of experience in valuation. Since that year, said standard has undergone revisions and modifications. The first was in 1999, the second in 2006 with a subsequent revision in 2007. The Granada Standard aims to standardize the considerations to take into account when evaluating a tree, palm, shrub, etc., to establish a coherent value, (based on numerous factors, aesthetic, functional, social, cultural …) that each valued individual contributes, as well as all of them in a specific environment.


This is the first and most important differentiation that this standard applies. Logically, the value of a tree will not be the same if it is a long-lived tree that cannot be replaced or it is a young tree that can be replaced. In the latter case, the basic value applied to this last tree will be the average value obtained from various nurseries that offer that specimen with the same characteristics. On the web you have numerous nurseries that offer their prices and product catalogs online.

In case of being  irreplaceable,  it is not possible to start from a basic value since there is no way to replace said copy, therefore the value contributed to that copy by the Granada Standard will be much higher. In this case, the Granada standard proposes measuring the perimeter of the trunk (in cm) at a height of 1m from the neck of the tree * .


Once the basic value (in replaceable) or the perimeter of the trunk at one meter from the neck (irreplaceable) has been obtained, a series of coefficients are applied based on a series of observations that we comment on below:


First, a suitability coefficient of the soil where the specimen is located is applied

Tree anatomy. (Covarrubias, 1991)

Then a coefficient must be established based on the climatic zone in which the tree or shrub is located.

  • Csa: Mediterranean subtropical climate
  • Csb: Temperate Mediterranean climate
  • Cfb: Humid temperate climate

From this moment the tree is evaluated for a series of intrinsic and extrinsic factors.

Intrinsic factors : Health status of the tree in each of its parts

  • Radical zone
  • Trunk
  • Main branches
  • Secondary and terminal branches
  • Sheets

Extrinsic factors : Representative values ​​in the environment, aesthetics, situation …)

  • Aesthetic and functional
  • Representativeness and rarity
  • Situation


Within this consideration, the standard divides the type of valuation based on whether it is for the purposes of simple valuation (knowing the value of the specimen), or for substitution purposes (value of the specimen plus the costs of removal, transport, land preparation, planting of the new specimen, expected percentage of rooting).
  • For valuation purposes:  Only the basic value corrected with the intrinsic and extrinsic coefficients mentioned above will be taken.
  • For substitution purposes: The final value will correspond to the previous value (for valuation purposes) plus the costs of eliminating the valued specimen, transport costs, preparation and conditioning of the land, official interest rate, maintenance cost of the tree grate and other costs. that are considered by the valuer.


There may also be the case in which it is not necessary to make an assessment by substitution, but simply an assessment of injuries or partial damages that have damaged the specimen. In this case, the Granada Standard does not take the basic value of the nursery as its replacement is not necessary. We are only assessing damage.

In this case, an assessment is made of the affected part, be it the trunk, the crown or the roots. The perimeter of the trunk is taken at 1m in height (as in irreplaceable) and the coefficients of soil suitability, intrinsic, extrinsic and climatic zone factors are applied.


The last part of the Granada Standard is the appraisal of shrubs which, although simpler, is not without value at all. In this assessment, not all the previous coefficients are taken into account since the shrubby part in most cases is easily substitutable. The valuation is made based on the market price of the species to be valued and the following is taken into account:

  • Cost of removing the item.
  • Cost of transportation.
  • Preparation and planting cost.
  • Official interest rate.
  • Pruning cost.
  • Tree maintenance cost.
  • Ideal age of the specimen to be appraised.
  • Age of the bush that we acquire in the nursery.
Once you read this, you will say to yourself: Very good, fantastic but… And the coefficients, where do I get them from, how do I apply them? Obviously there is a bibliography where you can consult them, but at Gardenprue we want to give you a very practical and simple solution. The AEPJP has developed a very simple form on its website in which to apply each and every one of the coefficients necessary for the assessment. You have to register and you will be able to use the tool as many times as necessary and even your evaluations will be saved in the system.
To start making an assessment for the Granada Standard, enter the AEPJP website . 
I lie, to start an assessment the first thing you have to do is GO TO THE PARK !. Identify the species, make a map of the situation, measure the trunks and above all, take a good camera and take a lot of photos of each tree.

* Note: The neck of the tree is defined as the point where the roots meet the trunk. Normally it will be the ground level, but in very long-lived specimens, for example, a large part of the roots may be exposed, leaving the neck higher than the ground level.

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