Freeze damage to tree fruit buds and blossoms

The Front Range is expecting a winter storm with temperatures expected to reach the low 20’s Fahrenheit, 3 to 5 below 0 Celsius. This event will likely cause significant bud and blossom death in fruit trees in this area, as well as to other fruits and vegetables. How much damage is determine by the specific plant (apple, peach, grape, spinach, etc) and the development stage.  There are methods to limit or prevent damage, and we recommend you do some research and apply as appropriate/reasonable to your specific plants, location and resources.  Mark Longstroth with Michigan State University Extension has a couple of tables with critical temperatures for tree fruits, which you can find here: http://msue.anr.msu.edu/news/freeze_damage_depends_on_tree_fruit_stage_of_development

This weather event is not expected to out right kill any apple trees on the Front Range, but local conditions and the health of individual trees vary, so it is possible.  We will keep an eye on our trees around Boulder County and certainly take note of this event.

Newly planted apple trees in Apple Valley

Twelve newly planted apple trees are now growing in Apple Valley, just west of Lyons, Colorado. A landowner contacted us a few months ago and we agreed on Central Asian apple trees. All are grafted, some last year, some this year, on Antonovka rootstock, and are therefore full sized trees when grown out. A neighboring landowner heard about the project and volunteered to take three trees, for a total of 12.  It was a beautiful day to be outside planting in beautiful Apple Valley, and the family living on the property did a lot of the heavy lifting to get the trees in the ground and are going to take great care of the trees in the coming years.  The land owner also did a lot of the heavy lifting and, key point here, made the property available for some trees.  The neighbors who took the three trees are master gardeners, and their property reflects the skills and effort required.

Apple Valley still has some apple trees, two in the immediate area, but not nearly as many as in the late 1800’s and early 1900’s.  We are hoping to change that, and are well on the way to doing so with this first planting.  There is a bit more room on the property, so we may be helping to get a few more in the new orchard.  Thanks to everyone involved.

Apple Valley Orchard

Apple Valley Orchard Location

Who’s doing what with apple biodiversity?

I thought it would be nice to have a list of projects working to protect apple biodiversity in North America (or elsewhere, if any readers can add information in the comments). Here’s a start:

  • Widespread Malus … that’s us! Working to build a highly diverse collection of Malus sieversii, as well as distribute scions, grafted trees, and seedlings.
  • Apple Diversity Group … a collaboration between Dalhousie University and Agriculture Canada, this group’s Apple Biodiversity Collection in Nova Scotia has 1000+ different apples, including about a hundred Malus sieversii.
  • USDA Plant Genetic Resources Unit … located in Geneva, NY, USDA PGRU maintains one of the world’s most extensive apple collections, including diverse wild apples (M. sieversii, M. orientalis, and others). Interested members of the public may request open-pollinated M. sieversii seed from PGRU.
  • Temperate Orchard Conservancy … located in Oregon, TOC is replicating the Botner Collection (perhaps the largest private collection of apples in the world … 4,500 different apples).
  • Montezuma Orchard Restoration Project … promoting apples and orchards in Montezuma County, Colorado and around the state. Also locating and propagating rare Colorado Heritage apples.
  • North American Fruit Explorers … a group of folks interested in all kinds of fruit. There are quite a few members with their own diverse collections of apples and other fruit. Visit the web site or the facebook page.
  • Seed Savers Exchange … not just for seeds! Iowa-based SSE has quite a nice collection of apples (hundreds), and numerous members who share apple scions with other members.
  • Agrarian Sharing Network … is sharing diverse fruit and vegetable material in the Pacific Northwest. ASN has done extensive evaluations and cloning of the Botner collection and several other large bioregional collections, and is involved in a number of propagation fairs.

Can you help us add more projects to this list? Please send us an email!

312 apples grafted, and counting!

We’ve got 200+ trees grafted for 63rd Street Farm, to be planted out later this month. Also, a few for giveaways, and maybe 50 Malus sieversii grafted from scions received from USDA in Geneva, NY. There are about 15 Antonovka rootstocks left to graft … most of these will be grafted with Malus sieversii.

2016 grafted apples.

2016 grafted apples.

Are you interested in a Malus sieversii tree for Spring 2017? Let us know if so!

The Andrus Orchard is ripped and disked

63rd Street Farm has ripped and disked between the rows of the orchard on the City of Boulder OSMP Andrus property.  The property was used to produce hay for many years, and the soil is fairly compacted.  This ripping and disking will disrupt the dense roots of the hay grass, loosen the soil and improve moisture penetration/retention.  It will also ease the planting and growing of the cover crop, which we are still discussing.  The ripping/disking is cross slope, so surface water moving downhill will be captured and move into the soil.  The flags in the image indicate tree locations.  Photo taken looking WWS.

IMG_20160311_132351347

New orchard at 63rd Street Farm, plotted and holes dug

The new orchard going in on the Andrus property, owned by the City of Boulder and managed by Open Space and Mountain Parks (OSMP), for 63rd Street Farm is well underway.  Working with 63rd Street Farm, we developed the orchard plan over the past 9 months and have reach two major milestones.  First, the orchard blocks were measured and plotted, using several different colored flags to outline the blocks and locate individual trees, by rootstock and wild/domesticated varieties.  Second, the holes were dug/bored.  The OSMP agriculture team was kept in the loop, ok’d all of the plans as well as provided a work team with bobcat to bore the holes.  The team was composed of the bobcat and operator and a work crew from the Boulder County Sheriff’s Office.  Thanks to both organizations, OSMP and Sheriff’s Office for boring the orchard tree holes.  This happened about a month ago, giving plenty of freeze/thaw cycles to work on the sides and bottom of the holes before the trees are planted in a few months.  This process, the freeze/thaw cycle, is important for this type of soil when holes are bored instead of hand dug.  The boring compacts the clay in the soil on the bottom and the sides.  If the bottom and sides are not broken up prior to planting, the hole tends to form a clay pot, constraining the tree roots and severely compromising the long term health and productivity of the tree.  Had we bored the holes in the spring, immediately prior to planting, we would have had to manually break up the bottom and sides of the holes.

The OSMP/BCSO team bore trees holes on the Andrus Property in late January 2016

The OSMP/BCSO team bore trees holes on the Andrus Property in late January 2016, they are nearly finished, working on the last of the holes in the western block of trees.  Photo is looking NNW

The western block of the Andrus Property, where the wild apple trees will be planted

The western block of the Andrus Property, where the wild apple trees will be planted.  Photo is looking close to due south

 

The orchard as planned will be 231 trees, with a mix of dwarf, semi-dwarf and full sized rootstock, and a wide mix of wild, dessert and multi-purpose apple varieties.  First to fruit will be the dwarf trees, which will be taken out as they are shaded by the full sized trees, in 10 to 15 years.

Next big step, grafting…

Malus sieversii from USDA … a Widespread Malus data compilation

FILE LINKS

This document in PDF format (100 kb)

Data compilation in Microsoft Excel format (962 kb)

Data compilation in Open Document Spreadsheet format (314 kb)

INTRODUCTION

Widespread Malus has compiled data on the USDA collection of Malus sieversii that might be useful in selecting accessions (scions or budwood) to request from USDA. We are collecting a ‘core diversity collection’ from the USDA collection that is especially diverse. Our goals are to make this diversity available to others, to grow out large number of open-pollinated seedlings, and make deliberate crosses with hand pollination in pursuit of useful new apple cultivars. However, there are a large number of other Malus sieversii in the USDA apple collection that will not be part of our diversity subset.

USDA’s Malus sieversii collection has enormous genetic diversity, and could serve as a useful reservoir of genes for use in breeding projects. There is already work being done in academia and by small numbers of nursery professionals and/or hobbyists.

We are hopeful that others can use this data compilation in their own work.

The data have been compiled into a Microsoft Excel format as well as Open Document Spreadsheet format (which may be opened by freely-available Open Office or its descendents). We may also make some data available in other formats. Inquiries regarding how to use the data are welcome.

We are responsible for any data-processing errors in this document, but we are not responsible for any requests you may make from USDA. We recommend that you cross-check your request with the GRIN database itself, and with the USDA Apple Catalog, to ensure you are requesting what you expect. Search the GRIN database at:

http://www.ars-grin.gov/npgs/searchgrin.html

Download USDA’s Apple Catalog from the link in the next section.

REQUESTING MATERIAL FROM USDA

Please consider carefully your ability to make use of any material you request from USDA. USDA personnel do an amazing job of maintaining this collection (and many others), often with limited resources. If you are not sure you can use what you are considering requesting, perhaps a request for this material isn’t the best use of your (or their) time.

USDA’s cutoff date for scion wood requests is January 10th (for shipment by March 20th). To request scion wood, you should download the USDA Apple Catalog, at:

http://www.ars.usda.gov/services/software/software.htm?modecode=80-60-05-00

There is a request form at the front of the catalog. The catalog is in Adobe Acrobat (PDF) format.

We had a bit of difficulty locating rootstock last month for March 2016 delivery, and suggest that you order ASAP if you have not yet done so. We ordered this year from Willamette Nursery and CopenHaven Farms (we received excellent rootstocks from Willamette in the past, and are ordering from CopenHaven for the first time this year, but are not recommending any particular nursery in this document).

In addition to, or instead of, requesting scions from USDA, you may wish to consider growing open-pollinated seedlings of Malus sieversii trees in the collection. If so, request "100 Open-Pollinated Malus sieversii seeds" on the order form. Requests for these seeds are typically filled with 25 seeds from each of four mother trees. If you are interested in cooperating with others to diversify the seeds you grow, please let us know. For example, we may be able to share seeds among several people so that instead of 25 seeds from each of four mother trees, each person ends up with 5 seeds from each of 20 mother trees. Pollen parents for these seeds are not known.

HOW THE DATA COMPILATION IS ORGANIZED

Not all USDA records for Malus sieversii are in the compilation. Both the USDA Apple Catalog and the GRIN page for each accession were examined. (see the BLUE-LETTERED columns in the image below. Y = available, N = not available, blank = no data) If the accession was in the GRIN database, but wasn’t indicated as AVAILABLE in the apple catalog or the accession’s GRIN page, it was not included. Some accessions were available as seeds and are available only for academic research; these were not included, either. Some accessions are listed in the GRIN page as "check regarding availability" — these are indicated with an M for maybe.

Note that the Apple Catalog and the GRIN page availability information may conflict. This is most likely due to GMAL accessions not being in the permanent catalog, and many/most of these GMAL accessions will be cut down during Winter 2015/2016 to make room for additional trees in the permanent collection. If you are interested in a GMAL accession that is not listed as being in the apple catalog, you should request it this year. We have inquired to make sure that trees have not yet been cut, but haven’t heard back by time of publication.

Apples that may be available from Widespread Malus are indicated in the RED-LETTERED column. However, quantities are extremely limited this year as we have barely begun our collection.

Screen shot from data compilation spreadsheet

The spreadsheet document has multiple "tabs" shown along the bottom. The first two, FULL SET BY PRIMARY ID and FULL SET BY BRIX contain all the records in the data set. Several other tabs (PARTIAL — FB RESISTANCE, PARTIAL — SCAB RESISTANCE, PARTIAL — ASTRIN. & BRIX>=11.5, and DIVERSITY CORE SETS) include only the relevant records. Two other tabs include descriptions of what data is in each column and references used in compiling this data set.

Negative 9 in a numeric column means NO DATA.

USING THE DATA COMPILATION TO FIND TREES OF INTEREST

  1. If you are interested in helping Widespread Malus build out diversity core set collections, you may want to request accessions from the DIVERSITY CORE SETS tab that we have not yet acquired. We may request scions of these accessions from you in the future, and of course you may request accessions from us. Would you like to coordinate requests for this material this year? Let us know … perhaps several requests can be coordinated to maximize the diversity of scions received.
  2. If you have other interests, we have provided several subsets of this data … for fireblight resistance, scab resistance, and astringent flavor with high BRIX. However, you can sort the data yourself if you are familiar with spreadsheet software.
  3. Are you willing to share scionwood or budwood with us or others? You are under no obligation to do so by using this compilation, but if you are willing, we’d love to know about it. Please let us know what you are requesting so that we know about it.
  4. If you need assistance sorting through the data, you’re welcome to contact us. We are not plant breeders, nursery professionals or biologists, but we’re happy to make suggestions if you’d like, based on the information in the data compilation.
  5. Note that a great number of the accessions that are available do not have any observations/attributes in the data set. Unless you are interested in rolling the dice to see what you get, these accessions will probably not be of use to you.

ONGOING COOPERATION/PARTNERSHIP WITH WIDESPREAD MALUS?

We welcome your interest in the genetic treasure that wild Malus sieversii represents. We all owe a great debt to USDA for making this material available, and to Central Asian nations who made it possible for USDA to acquire these trees.

We are promoting apple-growing more generally in the Boulder, Colorado area. We are also interested in cider making, providing educational opportunities regarding apples, and promoting native pollinator conservation through our orchard projects.

We hope you’ll keep up with our work at widespreadmalus.com or via Twitter (@widespreadmalus). Contact us by email at the addresses on the web site.