Conservation Evidence strives to be as useful to conservationists as possible. Please take our survey to help the team improve our resource.

Providing evidence to improve practice

Individual study: Ditch restoration in a large Northern Michigan fen: vegetation response and basic porewater chemistry

Published source details

Bess J.A., Chimner R.A. & Kangas L.C. (2014) Ditch restoration in a large Northern Michigan fen: vegetation response and basic porewater chemistry. Ecological Restoration, 32, 260-274


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Fill/block ditches to create conditions suitable for peatland plants (without planting) Peatland Conservation

A site comparison study in 2009–2011 in a fen in Michigan, USA (Bess et al. 2014) found that a ditch filled with peat spoil developed similar vegetation cover to undisturbed areas of the fen, but contained more plant species. After two years, the filled ditch and adjacent areas of undisturbed fen had similar cover of total vegetation (165 vs 180%), sedges (81 vs 80%), grasses (15 vs 10%), forbs (33 vs 20%) and bryophytes (29 vs 40%). However, there were more plant species in the filled ditch (49 species) than undisturbed fen (40 species). Results after one year were similar, except that the ditch had lower total vegetation cover than undisturbed fen (126 vs 188%) and lower bryophyte cover (18 vs 40%). In 2009, a ditch (dug in 2007 as a fire break) was filled with adjacent spoil (still moist and containing fen plant seeds). In 2010 and 2011, vegetation cover was recorded in sixty 1 m2 quadrats along the length of the ditch: 20 within it and 20 on either side. These were placed in areas not sown with additional seeds.

(Summarised by Nigel Taylor)

Introduce seeds of peatland trees/shrubs Peatland Conservation

A replicated, randomized, paired, controlled study in 2009–2011 in a fen in Michigan, USA (Bess et al. 2014) found that plots sown with shrub (and herb) seeds developed more vegetation cover overall than unsown plots, but similar cover of all monitored plant groups and similar species richness. After two years, sown plots had greater total vegetation cover (214%) than unsown plots (165%). Cover of individual plant groups did not differ significantly between sown and unsown plots (although it tended to be higher in the former): shrubs (4 vs 4%), sedges (120 vs 81%), grasses (27 vs 15%), forbs (28 vs 33%), bryophytes (33 vs 29%). The same was true for plant species richness (45 vs 43 species across all quadrats). Patterns were similar, but cover lower, one year after intervention. In 2009, twenty pairs of 9 m2 plots were established, in a ditch recently refilled with seed-rich fen spoil. Twenty plots (one random plot/pair) were sown with a mixture of shrub and herb seeds. The other 20 plots were not sown. The study does not distinguish between the effects of sowing shrubs and herbs. In 2010 and 2011, vegetation cover was recorded in one 1 m2 quadrat/plot.

(Summarised by Nigel Taylor)

Introduce seeds of peatland herbs Peatland Conservation

A replicated, randomized, paired, controlled study in 2009–2011 in a fen in Michigan, USA (Bess et al. 2014) found that plots sown with herb (and shrub) seeds developed more vegetation cover overall than unsown plots, but similar cover of all monitored plant groups and similar species richness. After two years, sown plots had greater total vegetation cover (214%) than unsown plots (165%). Cover of individual plant groups did not differ significantly between sown and unsown plots (although it tended to be higher in the former): sedges (120 vs 81%), grasses (27 vs 15%), forbs (28 vs 33%), mosses (33 vs 29%), shrubs (4 vs 4%). The same was true for plant species richness (45 vs 43 species across all quadrats). Patterns were similar, but cover lower, one year after intervention. In 2009, twenty pairs of 9 m2 plots were established, in a ditch recently refilled with seed-rich fen spoil. Twenty plots (one random plot/pair) were sown with a mixture of herb (grasses, rushes, sedges, forbs) and shrub seeds. The other 20 plots were not sown. The study does not distinguish between the effects of sowing herbs and shrubs. In 2010 and 2011, vegetation cover was recorded in one 1 m2 quadrat/plot.

(Summarised by Nigel Taylor)