Table 1 Gatherers’ perceptions of the optimal periods and environmental conditions for the growth of white truffles

1

Mid Sept-mid Jan; best time however is in November

Elm (Ulmus minor Mill.), Willow (Salix alba L.), Birch (Betula pendula L.), Oak (Quercus spp.)

Sandy soils “produce” round truffles; muddy soils flat and irregular truffles

Rain at the end of June-beginning of July is crucial for a good gathering season

2

Oct-Jan

Oak, Poplar (Populus spp.), Willow

Wet and ventilated soils; floods can stop the growth of truffles for many years

In July and August it must rain; snow in the gathering period does not have any influence

3

Mid Sept-mid Dec

Poplar, Lime Tree (Tilia platyphyllos Scop.), Dog Rose (Rosa canina L.), Cornelian Cherry Tree (Cornus mas L.), Willow, Pubescent Oak (Quercus pubescens Willd.)

Acidic soil; landslides stop the growth of truffles for a few years

Summer droughts generate very little growth in the fall

4

Aug-Jan

Elm, Oak, Birch, Willow

Wet and sandy soils; landslides and floods are very detrimental

Landslides and floods are very dangerous for the growth of white truffles, although they may be useful as well, since they shift and “reorganise” the occurrence of truffles elsewhere

5

Oct-Dec

Osier (Salix viminalis L.)

Pesticides and floods are very detrimental

Fresh and wet climate

6

Oct-Dec

Oak, Poplar, Hazelnut (Corylus avellana L.), Willow, Lime Tree

Soil exposure along the North-South direction

Wind occurrence

7.

End of Aug-beginning of Dec

Willow, Oak, Hazelnut

Fresh and wet soils

8

Aug-Dec

Poplar, Willow, Oak, Dog Rose

“Heathy” soils – a sign of these is the occurrence of many snails

Wet climate

9

Sept-Nov

Elm, Lime Tree, Pubescent Oak

Wet and fresh soils; windy slopes exposed to the North

Ventilated climate

10

Sept-Dec

Elm, Willow, Osier

Loam and slopes exposed to the North or South

11

Oct-Dec

Hazelnut, Poplar, Elm

Rocky soils

End of June it has to rain

12

Oct-Jan

Birch, Willow

The summer has to be rainy

13

Mid Sept-mid Dec

Pubescent Oak, Poplar, Lime Tree

Muddy and sandy soils, exposed to shadow

Windy climate

14

Sept-Jan

Oak, Hazelnut

15

Aug-Dec

Elm, Lime Tree, Oak

Wet and sandy soils

Heavy rains in July are crucial for a good season

16

Oct-Dec

Lime Tree, Elm, Birch, Poplar

Muddy and sandy soils exposed to the North

Wet climate

17

Sept-Jan

Osier, Willow, Poplar

Wet and sandy soils, rich in calcium

Rainy summer

18

Oct-Dec

Lime Tree, Elm, Hazelnut

Wet soils, far from vineyards and their chemicals/pesticides

Rainy summer