No. 65
Crabapple
Malus spp. (ornamental cultivars; native southern crabapple M. angustifolia and sweet crabapple M. coronaria)
Fruit ripe fruit (flesh; discard cores and seeds)
Drawing: Britton & Brown, Illustrated Flora (1913)
- Find
- Common in the right habitat
- Effort
- Real work
- ID risk
- Beginner
- Origin
- mixed
- Safety marks
- Toxic parts
- Uses
- Jam & jelly
- Juice & drinks
Season
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
in season peak
What these mean
Find
1 Everywhere · 2 Common in the right habitat · 3 Patchy · 4 Elusive. This is about how much there is, not whether you may pick it. It is based on iNaturalist sightings within 25 km (about 15 miles) of downtown DC, counted on October 3, 2026. The four rules that each plant’s “Find” reason refers to: (A) the estimate is the confirmed sightings, plus the unconfirmed ones (scaled down where the plant has lookalikes in its genus), plus the sightings marked as planted; (B) the tier by estimate: 1,500 or more is tier 1, 250–1,499 tier 2, 50–249 tier 3, under 50 tier 4; (C) tier 1, Everywhere, also needs a source saying the plant is common in lawns, sidewalks, yards or gardens, vacant lots or towns, or at least one DC street tree of it per km of sidewalk, otherwise it is tier 2; (D) if a reliable source says the plant is rare in this region, or that wild plants rarely bear the harvest, only planted sightings count. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.
Effort
1 Grab & eat · 2 Quick kitchen prep (under about 30 minutes) · 3 Real work (hours, or cooking needed for safety) · 4 Project (days or equipment). Scored on the simplest worthwhile use; each plant’s page says why.
ID risk
How hard it is to harvest safely. Beginner: no dangerous lookalike, and the edible part is not easily confused with a toxic part. Careful: a toxic lookalike, or toxic parts that end up in the harvest unless removed (for example elderberry stems, unripe ground cherries), or other parts of the plant rated medium-or-higher toxicity, with reliable features to separate them. Expert only: a potentially deadly lookalike that is hard to separate, or (for not-recommended harvests like pokeweed) a plant whose safe preparation can’t be guaranteed. Toxic parts that are obviously separate and thrown away anyway (pits, seeds, skins) don’t raise it; the Toxic parts mark carries that warning.
Native or not, and the invader stars
Origin is where the plant comes from: native, non-native, or mixed (the harvest covers both). The stars rate plants on invasive plant lists: ★★★ Virginia DCR “High” or Maryland prohibited invasive · ★★ Virginia “Medium” · ★ Virginia “Low” · ☆ listed only by the Maryland Invasive Species Council or the Mid-Atlantic Plant Invaders guide (advisory) · no stars: native or not listed.
Safety marks and flags
Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger. Deadly means a source says eating it may be fatal or calls it deadly, or NC State rates it high severity with life-threatening symptoms (sources sometimes disagree; for example Virginia creeper). Each plant’s Lookalikes list says how to tell them apart; “harmless (may be edible)” lookalikes are listed so you know a mix-up isn’t dangerous. Cook first: cooking is needed for safety (for daylilies it is a precaution, not a sourced requirement). Eat in moderation: a source says to limit quantity or frequency (for example oxalates in sorrels and dock, ginkgotoxin, safrole). Spray risk: a source says the plant is commonly treated with herbicide in parks or lawns (invasive control, lawn weeds) or, for ginkgo, sprayed to stop fruiting. Contamination: a source says the plant concentrates pollutants. Each plant’s Safety flags list gives the details and sources.
Seasons
Start, peak and end are given in thirds of a month: early, mid or late. A plant counts as in season for a month if it is in season at any point in that month. Some greens and roots have a second window, in spring or fall; their page shows each window. A season that runs across New Year is shown as one window.
What it looks like
Small apple trees with showy spring blossoms. Any apple 2 inches across or smaller counts as a crabapple. The fruit ranges from pea-size to about 2 inches and can be yellow, orange, red or maroon. Most are hard and very tart raw. They are rich in pectin and become more palatable after a few freeze-thaw cycles.
Safety
Seeds and leaves contain the cyanogenic glycoside amygdalin. NC State rates the risk as low, since harm takes a large quantity of seeds, and for jelly or pectin the whole fruit is simmered and strained, so the seeds stay behind (NCHFP’s tested crabapple jelly uses uncored fruit). Don’t crush or eat the seeds. Ornamental trees are often sprayed, so pick only from trees you know are pesticide-free (NC State). Only eat fruit from trees you are sure are Malus (Iowa State: if you are unsure of a tree’s identity, do not eat the fruit).
Safety flags
Toxic parts
Seeds and leaves contain amygdalin; NC State rates the risk low since harm takes a large quantity of seeds.
Safety marks and flags: what this means
Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger. Deadly means a source says eating it may be fatal or calls it deadly, or NC State rates it high severity with life-threatening symptoms (sources sometimes disagree; for example Virginia creeper). Each plant’s Lookalikes list says how to tell them apart; “harmless (may be edible)” lookalikes are listed so you know a mix-up isn’t dangerous. Cook first: cooking is needed for safety (for daylilies it is a precaution, not a sourced requirement). Eat in moderation: a source says to limit quantity or frequency (for example oxalates in sorrels and dock, ginkgotoxin, safrole). Spray risk: a source says the plant is commonly treated with herbicide in parks or lawns (invasive control, lawn weeds) or, for ginkgo, sprayed to stop fruiting. Contamination: a source says the plant concentrates pollutants. Each plant’s Safety flags list gives the details and sources.
- ID risk
- Beginner
- Why
- The apple-shaped fruit is distinctive. Iowa State’s rule is to eat only from trees you are sure are Malus; seeds are low-risk and removed in cooking.
- Soil risk
- low
ID risk: what this means
How hard it is to harvest safely. Beginner: no dangerous lookalike, and the edible part is not easily confused with a toxic part. Careful: a toxic lookalike, or toxic parts that end up in the harvest unless removed (for example elderberry stems, unripe ground cherries), or other parts of the plant rated medium-or-higher toxicity, with reliable features to separate them. Expert only: a potentially deadly lookalike that is hard to separate, or (for not-recommended harvests like pokeweed) a plant whose safe preparation can’t be guaranteed. Toxic parts that are obviously separate and thrown away anyway (pits, seeds, skins) don’t raise it; the Toxic parts mark carries that warning.
Soil risk: what this means
Based on the part you eat, following the urban-soil lead guidance on the Field safety page: higher for greens, shoots and roots; moderate for flowers; low for fruit, nuts and sap.
Field safety for every outing (poison ivy, ticks, soil, and more)
When to pick
- Starts
- late Aug
- Peak
- late Sep–late Oct
- Ends
- late Feb
Timing varies a great deal by cultivar: some ripen in August and others in fall (Iowa State). The native southern crabapple shows fruit August to September (NC State). Many ornamental cultivars hold their fruit through the winter, and the fruit becomes more palatable after a few freeze-thaw cycles (Penn State Extension). Birds eat crabapples through the winter and save the sourest ones for early spring, so how much is left by late winter depends on the tree (Penn State Extension). Larger-fruited trees are best for the kitchen (Iowa State).
How the dates were worked out
Every start, peak and end was re-checked in October 2026. “Sourced” means a source opened during the check states that timing for the DC or Mid-Atlantic area. “Estimated” means no source states it exactly; the reason, the evidence and the source links are under “How the dates were worked out” on each plant’s page. Peaks are often estimated, because few sources name a peak. iNaturalist evidence means research-grade sightings near DC, by month, of the plant at that stage (for example, in fruit). iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.
Season basis: estimated: start, peak, end
Start
estimated: August is sourced but not for DC specifically; late Aug marks the early cultivars.
Peak
estimated: No source gives a peak; counts are too small to define one, so the peak is set to the fall months most cultivars mature in.
End
estimated: Penn State says 'through the winter' without a date; late Feb is the end of winter, and what is left by then depends on the cultivar and on birds.
Evidence
start: NC State (NC, with a note): southern crabapple 'Fruits display from August to September'. Iowa State: 'The fruit of some crabapple varieties color and ripen in August, and others mature in the fall.' iNaturalist cultivated Malus (excluding domestic apple) within 25 km of DC: fruiting records in weeks 31 and 33 (early-mid Aug). | peak: Iowa State: many varieties 'mature in the fall'. iNaturalist Malus (excl. domestic apple) within 25 km of DC: research-grade fruiting Sep 3, Oct 1; cultivated fruiting Aug 3, Oct 3, Nov 2. | end: Penn State Extension: 'many varieties hold their fruit through the winter'; the fruit is 'very hard at first, but become[s] more palatable after a few freeze-and-thaw cycles'; 'Prairiefire' and 'Sugar Thyme' fruit 'persist through the winter', 'Sentinel' into December. iNaturalist cultivated Malus near DC: a fruiting record in January (week 2).
- Malus angustifolia NC State Extension Plant Toolbox
- Edible Fruit on Ornamental Trees and Shrubs Iowa State University Extension (Yard and Garden)
- api.inaturalist.org/v1/observations/histogram
- api.inaturalist.org/v1/observations/histogram
- Crabapple (Malus, excluding domestic apple) cultivated fruiting observations within 25 km of DC, by month iNaturalist
- There’s a Flowering Crabapple for That Penn State Extension
Where to look
Ornamental crabapples fill yards, campuses and parks (iNat misses most planted trees), so ask owners; logged trees in Sligo Creek and Rock Creek parks are no-picking, and those at Dumbarton Oaks are in Harvard’s private gardens (ask the owner), and the C&O/NACE 'apples' wording only ambiguously covers crabapples.
- Habitats
- street & yard trees (planted)
Habitats: what this means
Listed where the plant’s own sources place it in that habitat. “Disturbed ground & waste places” means a cited source places it on disturbed areas, sites, soil or ground, on waste places or waste ground, on construction or abandoned building sites (old home sites count), on rubble or in strip mines. When the source gives examples of the disturbed places, at least one example must be of that kind. Examples that do not count: natural or forestry disturbance (treefall gaps, fire, windthrow, flood scour, old riverbanks and creeks, clear-cuts); roadsides, railroads and rights-of-way; and abandoned fields, pastures and farmland, which are “Old fields & meadows”. “Vacant lots” only where a source says vacant or empty lots.
Most-logged places
None of the most-logged places allows picking.
Ask first: rules unclear or not checked
- Wheaton Branch Stormwater Ponds (Montgomery County land)
Montgomery County stormwater land, not M-NCPPC parkland; picking rules not checked. iNaturalist’s outline also takes in nearby homes, churches and homeowners'-association land.
No picking here (4 places)
- Rock Creek Park
Look but don’t pick: Rock Creek Park’s compendium bans gathering any fruit, nut, berry, seed or greenery.
- Cabin John Regional Park
Look but don’t pick: Montgomery/Prince George’s parks (M-NCPPC) ban harvesting vegetation without a permit.
- Dumbarton Oaks gardens (Harvard University, private)
Private property: pick only with the owner’s permission.
- Sligo Creek Stream Valley Park
Look but don’t pick: Montgomery/Prince George’s parks (M-NCPPC) ban harvesting vegetation without a permit.
Most-logged places: what this means
The places with the most research-grade iNaturalist sightings within 25 km of downtown DC (re-counted in October 2026 over every named place, campuses, condominiums and private grounds included), each marked legal to pick or not. A sighting inside several named places counts once, for the smallest of them, but a sighting inside a National Park Service park never counts for a private, campus or unchecked place. iNaturalist shows where people walk and log plants, not true abundance. Private campuses, condominiums, museums, estates and utility land (Pepco’s power-line land near Sligo Creek) are marked “no” (pick only with the owner’s permission); public university campuses, city parks and other places whose picking rules were not checked (county stormwater land, the U.S. Capitol Grounds, Greenbelt’s North Woods, federal facilities such as the National Zoo) are “unknown”. A place needs at least 2 sightings, so plants with very few sightings (rugosa rose) have no places. No most-logged places are named for at-risk plants (ramps, chinquapin, American chestnut); chinquapin’s page names Mason Neck State Park, where picking is legal, and asks you to leave most nuts. For some places, mostly Rock Creek Park, the iNaturalist map shows more sightings than the count here, because a map link cannot leave out exactly the sightings credited to another place. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.
Where you may pick
C&O Canal NHP allows apples for personal use (1 bushel per person per day). The compendium says 'apples' and does not mention crabapples specifically, so crabapple’s status there is ambiguous: confirm with the park. Rock Creek Park and its DC units ban all gathering.
- C&O Canal NHP (incl. Great Falls MD, trail-side only)
C&O Canal compendium (eff. Sept. 11, 2026) 2.1(c)(1), daily per-person limits: apples: 1 bushel. Crabapples are Malus, but the compendium says only 'apples' and does not say whether crabapples are meant
- National Capital Parks-East (listed sites only)
NACE 2026 compendium 2.1(c)(1), (c)(2)(ii): designated items are blueberries, blackberries, grapes, pawpaws, raspberries, walnuts and apples (apples not at Oxon Hill Farm), in amounts under one quart, at seven listed areas; covers apples. Crabapples are Malus, but the compendium says only 'apples'; not at Oxon Hill Farm
- Prince William Forest Park
PRWI compendium (May 29, 2026) 36 CFR 2.1 'Plant Collection': 'apples (Malus spp.) or (Pyrus spp.)'; the genus-level listing covers crabapples
- Virginia State Parks
4VAC5-30-50 bars gathering any plant without a permit, except that edible fruits, berries, fungi or nuts may be collected for personal or individual use; crabapple is an edible fruit
Where you may pick: what this means
For each park system: “yes” where its current rules (the park’s compendium or regulation) allow this plant or part, with the limit; “ambiguous” where the wording may or may not cover it, so ask the park; “no” where it is not allowed. Rock Creek Park, the GW Parkway sites (including Great Falls VA and Theodore Roosevelt Island), the National Mall, Montgomery and Prince George’s parks, Maryland state parks, and Fairfax and Arlington parks prohibit picking. Wolf Trap National Park for the Performing Arts allows blackberries and raspberries (one gallon per person per day) and chestnuts (one gallon per person per day). National Park Service rules are reissued every year; other parks change theirs from time to time, so check the park’s current rules. The Where you may pick page has every park’s rules.
Ways to use it
- crabapple jelly (large-fruited types such as 'Whitney' and 'Chestnut' are best)
- homemade pectin: simmer whole crabapples in water, strain, and use the liquid to set low-pectin fruits (University of Saskatchewan)
- preserves, juice and cider
- use in place of apples in cooked recipes
- spiced crabapple preserves: whole crabapples canned in spiced syrup (NCHFP has a tested boiling-water canning recipe)
Keeping
Firm fruit keeps a week or more refrigerated, so make jelly within a couple of weeks using NCHFP’s tested crabapple jelly recipe.
- Use within
- weeks
- Keeps fresh
- General guidance for apples: hold slightly underripe fruit somewhere cool; once ripe, it keeps a week or longer in the refrigerator crisper or a plastic bag. Use bruised fruit first (University of Kentucky).
- Canning
- lab-tested: jelly, spiced whole crabapples (NCHFP)
- Keeping basis
- general guidance for its type
Ways to keep it
Can as researched: can (water bath); canning: lab-tested: spiced whole crabapples (NCHFP)
NCHFP has tested spiced-crabapple recipes for boiling-water canning.
Freeze as researched: freeze; canning: n/a (not shelf-canned)
General guidance for apples: freeze slices treated against browning (NCHFP freezing apples).
Jam/jelly as researched: jam/jelly; canning: lab-tested: jelly (NCHFP)
NCHFP’s tested crabapple jelly without added pectin uses about 1/4 firm-ripe and 3/4 fully ripe fruit, unpeeled and uncored, processed 5 minutes for half-pints or pints at 0-1,000 ft.
Canning: what this means
Shelf-stable canning, three levels. Lab-tested: a lab-tested recipe from the National Center for Home Food Preservation (NCHFP) or Oregon State covers this fruit and product, or a generic recipe for its kind (the line says so, for example chokeberry). Extension recipe: a published Extension recipe (University of Alaska Fairbanks, written for Alaska species; University of Maine’s dandelion jelly), or a process that is safe only with a pH meter; follow it exactly, never improvise. No tested recipe: refrigerate or freeze, don’t can. “Hot-bottled syrup” = maple and walnut syrup, which keep when bottled hot at full syrup density. The Canning line names the exact product each source covers, for example “whole berries” or “juice”; a product not named there (such as juice from a berry with only a whole-berry recipe) has no tested recipe.
Keeping basis: what this means
“Specific to this plant” or “general guidance for its type” (for example NCHFP guidance for leafy greens applied to a wild green).
Nutrition
Not researched: in October 2026, only the calendar’s plants of the month and chicory leaves were researched.
Native or not
Mixed genus. Native: southern crabapple M. angustifolia and sweet crabapple M. coronaria (USDA PLANTS: native). Introduced (USDA PLANTS): ornamental Japanese flowering crabapple M. floribunda, Siberian crabapple M. baccata, Toringo crabapple M. toringo (syn. M. sieboldii), and escaped apple M. pumila. Most planted ornamental crabapples in DC are Asian species/hybrids. No Malus species appears on the VA DCR, MDA or MISC lists.
- Origin
- mixed
- Native range
- mixed: ornamental crabapples are Asian/Eurasian; native southern crabapple (M. angustifolia) and sweet crabapple (M. coronaria) are eastern North America
- Virginia invasive rank
- not listed
- Maryland invasive status
- not listed
Native or not, and the invader stars: what this means
Origin is where the plant comes from: native, non-native, or mixed (the harvest covers both). The stars rate plants on invasive plant lists: ★★★ Virginia DCR “High” or Maryland prohibited invasive · ★★ Virginia “Medium” · ★ Virginia “Low” · ☆ listed only by the Maryland Invasive Species Council or the Mid-Atlantic Plant Invaders guide (advisory) · no stars: native or not listed.
Virginia DCR, Virginia Invasive Plant Species List (effective September 2024), verbatim: "Under the DCR Invasive Species Assessment Protocol, approved by the Virginia Invasive Species Working Group, January 2024, species were ranked as exhibiting high, medium or low levels of invasiveness based on their threat to natural communities and native species. Invasiveness rank is higher for species that: • Alter ecosystem processes, such as succession, hydrology or fire regime. • Are capable of invading undisturbed natural communities. • Cause substantial impacts on rare or vulnerable species or natural communities or high-quality examples of more common communities. • Are found widely distributed and generally abundant where present. • Disperse readily to new areas. • Are difficult to control." The list also states: "The list is for educational purposes only and has no regulatory authority."
Maryland Department of Agriculture, Maryland Prohibited Invasive Plant Law and Regulations page, verbatim: "Plants on the Maryland Prohibited Invasive Plant List may not be added to stock after the effective date and should not be sold after their phase-out period ends."
No official DC invasive plant list was found.
How the ratings were set
- Find
- Common in the right habitat Estimate 1,436 = 42 research-grade iNaturalist sightings within 25 km + 1,493 needs-ID sightings counted at 70% (in the October 5 genus count, 42 of the 60 research-grade Malus sightings here were crabapples (Malus other than domestic apple)) + 349 'cultivated' (planted) sightings (rule A); that is tier 2 by count (rule B). Domestic apple (Malus domestica, 18 research-grade sightings) is not counted. Final tier 2.
- Effort
- Real work Crabapple jelly: wash, simmer whole fruit, strain the juice (cores and seeds stay behind), then boil with sugar and jar; Iowa State does not describe eating them raw.
Find: what this means
1 Everywhere · 2 Common in the right habitat · 3 Patchy · 4 Elusive. This is about how much there is, not whether you may pick it. It is based on iNaturalist sightings within 25 km (about 15 miles) of downtown DC, counted on October 3, 2026. The four rules that each plant’s “Find” reason refers to: (A) the estimate is the confirmed sightings, plus the unconfirmed ones (scaled down where the plant has lookalikes in its genus), plus the sightings marked as planted; (B) the tier by estimate: 1,500 or more is tier 1, 250–1,499 tier 2, 50–249 tier 3, under 50 tier 4; (C) tier 1, Everywhere, also needs a source saying the plant is common in lawns, sidewalks, yards or gardens, vacant lots or towns, or at least one DC street tree of it per km of sidewalk, otherwise it is tier 2; (D) if a reliable source says the plant is rare in this region, or that wild plants rarely bear the harvest, only planted sightings count. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.
Effort: what this means
1 Grab & eat · 2 Quick kitchen prep (under about 30 minutes) · 3 Real work (hours, or cooking needed for safety) · 4 Project (days or equipment). Scored on the simplest worthwhile use; each plant’s page says why.
Sources
28 sources, each linked to the original.
- C&O Canal NHP Superintendent’s Compendium National Park ServiceBacks up: picking rules
- Rock Creek Park Superintendent’s Compendium National Park ServiceBacks up: picking rules
- iNaturalist research-grade observations of Malus (genus, excluding domestic apple M. domestica) within 25 km of downtown DC iNaturalistBacks up: findability
- Apples (Plate It Up commodity page) University of Kentucky Cooperative Extension, Family and Consumer SciencesBacks up: keeping
- Crabapple Jelly without Pectin National Center for Home Food Preservation (Univ. of Georgia)Backs up: keeping
- Making Jelly without added Pectin National Center for Home Food Preservation (Univ. of Georgia)Backs up: keeping
- Freezing Apples National Center for Home Food Preservation (Univ. of Georgia)Backs up: keeping
- USDA PLANTS Database: Malus angustifolia (MAAN3), native status USDA NRCSBacks up: native or invasive status
- USDA PLANTS Database: Malus coronaria (MACO5), native status USDA NRCSBacks up: native or invasive status
- USDA PLANTS Database: Malus pumila (MAPU), native status USDA NRCSBacks up: native or invasive status
- USDA PLANTS Database: Malus floribunda (MAFL80), native status USDA NRCSBacks up: native or invasive status
- USDA PLANTS Database: Malus baccata (MABA), native status USDA NRCSBacks up: native or invasive status
- USDA PLANTS Database: Malus toringo (M. sieboldii) (MASI80), native status USDA NRCSBacks up: native or invasive status
- Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
- Maryland Prohibited Invasive Plant Law and Regulations (Maryland Prohibited Invasive Plant List, updated January 2026; additions effective July 15, 2026; 'Next Plants To Be Assessed' 2026-2027) Maryland Department of Agriculture, Plant Protection & Weed ManagementBacks up: native or invasive status
- Non-Native Invasive Terrestrial Plant Species in the State of Maryland (updates approved through the April 18, 2024 MISC meeting) Maryland Invasive Species CouncilBacks up: native or invasive status
- Plant Invaders of Mid-Atlantic Natural Areas, Field Guide (Swearingen & Fulton, 2022; successor to the NPS/USFWS 5th ed., 2017) Mid-Atlantic Invasive Plant Council / Passiflora Press (hosted by Bugwood/Mid-Atlantic Invaders Tool)Backs up: native or invasive status
- Invasive Plants in the District DC Department of Energy & EnvironmentBacks up: native or invasive status
- Amygdalin: Toxicity, Anticancer Activity and Analytical Procedures for Its Determination in Plant Seeds Molecules (via PubMed Central, NIH)Backs up: safety
- Malus sylvestris NC State Extension Plant ToolboxBacks up: safety, uses, description
- Crabapple (Malus, excluding domestic apple) cultivated fruiting observations within 25 km of DC, by month iNaturalistBacks up: season
- There’s a Flowering Crabapple for That Penn State ExtensionBacks up: season, description, habitat
- Malus angustifolia NC State Extension Plant ToolboxBacks up: season, description, habitat, uses
- Is it ok to eat crabapples? Iowa State University Extension (Yard and Garden)Backs up: season, description, uses
- Edible Fruit on Ornamental Trees and Shrubs Iowa State University Extension (Yard and Garden)Backs up: season, description, uses, safety
- Make your own pectin from crabapples University of Saskatchewan (Gardening at USask)Backs up: uses
- Wild Edibles of Missouri (Jan Phillips, 2nd ed.) Missouri Department of ConservationBacks up: uses
- Crabapples-Spiced (canning) National Center for Home Food Preservation (Univ. of Georgia)Backs up: uses, keeping