At this time of year, I quite often write about the autumn harvest of hips, haws, berries and nuts and this year’s harvest seems to be especially bountiful.
It’s been widely reported that this year is a ‘mast’ year – something that only occurs every few years – and whilst familiar with the term, I wasn’t entirely clear on what distinguishes a normal autumn harvest from a mast year and what might trigger them.
All trees and shrubs produce seed as part of their survival strategy. Over millennia, different species have evolved an array of seeds in all shapes and sizes and utilise different approaches to get their seed spread far and wide. The seeds of trees such as ash are designed to catch the wind as they fall, carrying them beyond the shadow of the parent tree. Others, such as rowan, develop berries that are eaten by birds and other wildlife – resulting in their seeds being deposited far and wide.
The collective term for different forms of seeds, nuts and berries is ‘mast’ – derived from the old English maest meaning fruits of the forest that have gathered on the ground. Whilst the volume of seed produced year on year varies greatly, years with a particularly plentiful crop are considered to be mast years.
As is often the case with nature, we don’t yet fully understand what causes these fluctuations, but we know that weather plays a part. For example – whilst an oak tree will produce a similar number of flowers each year, the number that get pollinated and produce viable seed is affected by the weather, with warm, dry springs promoting greater pollination.
Seed volumes are also affected by the availability of water, nutrients and carbon in any given year. The hugely varying cycle is also thought to have been an evolved response to try and limit the impact of ‘predators’ – in the form of animals that eat the seeds. Whilst lean years help limit the number of predators, mast years help ensure a supply escapes the clutches of hungry hoards. Whilst we now understand some of the triggers and evolutionary motivations behind mast years, much mystery remains. This is especially true in terms of how trees communicate to coordinate what otherwise appear to be random occurrences.
The fact that there is still much to learn about the rhythms of nature is part and parcel of why nature is so inspiring and intriguing. Whatever the evolutionary or environmental triggers, we know that many animals benefit from mast years – with jays, wood mice, badgers, deer and others taking advantage of the energy packed harvest. We too enjoy the sight of nature’s bounty, the bustle of activity it brings as creatures clamour to gorge themselves and, as long as we remain mindful of only taking our fair share, we can also partake in enjoying the ‘fruits of the forest’. Foraging for edible nuts such as hazelnuts or turning bitter, unpalatable berries such as sloes, into seasonal tipples to enjoy in the depths of winter as we long for spring to return is a great way to reconnect with nature and we can also look forward to spotting verdant saplings arising from the leaf litter next spring as the ancient cycle begins once more.
Stay connected
Throughout the year, Nottinghamshire Wildlife Trust hosts a range of events designed to help you discover and connect with nature – including a fascinating programme of talks hosted by our local members’ groups across the county. Details of all events, as well as our wonderful nature reserves can be found at www.nottinghamshirewildlife.org.
Image: Wood mouse, Sean Browne