LIFE OrnamentalIAS: Green waste and invasive plant species management

To better understand the issue, our project conducted a survey among 52 garden owners in May and June 2024 about the management of green waste and the mapping of green pruning waste dumps in the area around 16 settlements in the park.

Size and amount of green pruning waste:

• Size of gardens: The respondents' gardens varied in size, from as small as 10 m² to as large as 5,000 m². The average size was 1,088 m².
• Quantity of green waste: The annual amount of green waste per garden ranged from 0.1 m³ to 36 m³, averaging 3.4 m³ per year.

Methods of handling green waste: Respondents used different methods for handling green waste. Almost half (48%) used multiple methods simultaneously:

• Garden compost heap: 48% of respondents
• Burning in the garden: 17% of respondents
• Landfill on the edge of the village: 12% of respondents
• Grazing/feed for livestock: 8% of respondents
• Biowaste container: 7% of respondents
• Municipal collection center: 7% of respondents
• Wood chips for heating: 1% of respondents

Yellow-orange daylilies (Hemerocallis fulva) that have escaped into the wild.

Presence and diversity of hedges:

• hedge: 36 respondents (69 %) have a hedge planted in their garden; one respondent had a hedge in the past, but no longer has it.
• Species in the hedge: A total of 33 different tree species were recorded in the hedge, an average of 2.4 species per respondent.
  Most common species:
• Bay laurel: 38 %
• Privet (ligustrum): 32 %
• Klek (cypress): 30 %
• Cotoneaster: 14 %
• Hazel, spruce, Spanish elder: 11 %

Presence of invasive alien plants (IAP):
Respondents with IAP: 22 respondents (42 %) had at least one of the ten invasive plants listed in the survey.

Number of different IAP species in the garden:

• One species: 9 respondents (17 %)
• Two species: 6 respondents (12 %)
• Three species: 5 respondents (10 %)
• Four species: 1 respondent (2 %)
• Six species: 1 respondent (2 %)

Most common IAP in the gardens:

• Yellow daylily: present in 25 % of gardens
• Butterfly bush (Buddleja): 15 % of gardens
• Vinca (periwinkle): 12 % of gardens
• Rudbeckia: 10 % of gardens
• Gray dogwood: was not present in any garden

Sevenoaks aster (Symphyotrichum sp.).

These results highlight the diversity of green waste management practices and the presence of invasive plants in the Notranjski Park area. Awareness of these practices and the presence of invasives is crucial for developing strategies to manage and reduce their impact on local biodiversity.