| Country of the unit : | Italy |
| Unit number: | ITA00045 |
| National gene conservation unit number: | ITACU045 |
| Province or state: | Lombardy |
| Department or county: | Pavia |
| Municipality: | Pavia |
| Local name : | Riserva naturale integrata di Siro Negri |
| Latitude : | 45°12'33"N |
| Longitude : | 9°3'30"E |
| Restriction in making the geographical coordinates publically available: | 0 |
| Datum: | |
| Polygon coordinates (if available): | |
| Minimum elevation (m): | 100 |
| Maximum elevation (m): | 100 |
| Surface area of the unit (ha): | 11 |
| Ownership of the unit : | Public |
| Type and function of the unit : | Gene reserve forest; Biodiversity conservation (habitats AND/or species) |
| Monthly temperature (°C): | |
| Total annual mean precipitation (mm): | |
| Heat sum and/or length of the growing season (in days): | |
| Accumulated moisture deficit: | |
| Year of collection of the field data entered: | 2002 |
| Year of the most recent visit: | 2005 |
| Remarks on specific soil characteristics: | |
| Remarks on other specific characteristics of the unit: | |
| All tree species growing in the unit: | Populus alba; Quercus robur; Populus nigra |
| Target species: | Populus nigra |
| National population unit number if existing: | |
| Year of establishment of the GCU for the species: | 1973 |
| Year of the most recent visit: | 2005 |
| Status of the target tree population regarding the EUFORGEN common action plans.: | |
| Category of the population: | In situ |
| Origin of the material: | Autochtonous |
| Predominant silvicultural system: | No silviculture |
| Level of management allowed to favour the target species: | No intervention allowed |
| Main reason for carrying out gene conservation for this species: | To conserve specific adaptive and/or phenotypic traits in marginal or scattered tree populations which are often relatively small |
| Total number of reproducing trees per unit: | 50 - 499 |
| Sex ratio, if appropriate: | |
| Status of long-term viable regeneration : | |
| Distribution of the reproducing trees in the unit (multiple choice): | Scattered |
| Estimated share of the total area within the unit in which the species is occurring (%): | 100 |
| Remarks on the population: | |