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| ====== broom ====== | ====== Witch's Broom ====== |
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| ===== Overview ===== | ===== Description ===== |
| Broom (often referred to as Witch's Broom or WB) is a highly debated cactus condition characterized by abnormal, dense, and clustered growth. It is a significant concern for growers because of its potential to spread and infect entire collections, though it is frequently confused with benign genetic mutations or localized pest damage. | Witch's Broom is a pathological condition and growth symptom in cacti, characterized by highly abnormal, hyper-clustered growth. It affects various species, including //Trichocereus// and //Lophophora//. This pathogen is highly contagious and spreads rapidly through collections. It is not curable, and left to run its course eventually ends in plant death. |
| | * **Rib Count:** In affected areas, distinct ribs are typically absent or highly reduced due to the extreme density of the stacking growth points. |
| | * **Spines:** Spines on the clustered pups are often miniature, dense, and can range from light yellow to brown, though they are frequently obscured by excessive areolar wool. |
| | * **Epidermis:** The epidermis remains light to dark green in early onset but turns yellow to red as the disease progresses and growth outpaces nutrient availability. In heavily afflicted areas the epidermis is heavily crowded by the rapid proliferation of new shoots. |
| | * **Areoles:** Areoles in the affected zones often produce an abundance of dense white fluff or wool. |
| | * **Foolproof tell:** Pups on pups on pups. Pups coming out of every areole of other recent pups. |
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| ===== Symptoms & Identification ===== | =====Origin ===== |
| * **Extreme Clustering:** True broom causes highly congested, clustered growth. According to Thomas Lauritzen, actual Witch's Broom will be at least "3X" more clustered than typical funky growth. | * **Pathological Origin:** True Witches Broom is caused by a Mycoplasma-Like Organism (MLO), a type of phytoplasma. |
| * **Hormonal Changes:** The condition affects the plant's hormone levels, sometimes causing a plant to revert or throw an unusual abundance of pups. | * **Pest Induced spread:** The phytoplasma infection can spread from insects feeding on afflicted plant areas, then feeding on other healthy plants. |
| * **Common Confusions:** Broom is easily confused with: | |
| * Normal new growth on monstrose or crested cacti (such as *Olivia x Jess*), which can look highly irregular at an early stage. | |
| * Active growth points or mutations. | |
| * Scarring and abnormal growth patterns resulting from localized bug damage. | |
| |
| ===== Cause & Spread ===== | ===== Commonly confused with ===== |
| The exact pathogen or underlying cause of broom remains unconfirmed in community discussions, though several factors are suspected: | * **Monstrose growth:** This condition is easily confused with natural monstrose, crested, or caespitose growth forms (such as //Lophophora williamsii f. caespitosa//). Certain monstrose genetic lines, such as crosses involving the cultivar "Olivia", are highly prone to throwing funky, clustered growth that can be confused with Witch's Broom. |
| * **Stress:** Some growers believe the condition can be triggered by general plant stress. | * ** Pest damage:** Non-infectious broom-like growth can be triggered by physical damage to the meristem. Sucking pests like mealybugs, mites, or caterpillars can damage the growing tip, causing it to terminate and throw a dense cluster of lateral pups. If pests are treated growth will eventually return to normal. |
| * **Pests:** Bug damage is heavily associated with the onset of broom-like growth. Bob Makershoe noted that while some abnormal growth is direct bug damage, "so is broom," suggesting a pest vector or pest-induced origin. | |
| * **Spread:** If it is true broom, the condition is reported to be highly infectious. ScrapGoat Benjamin warned that letting the condition go untreated can result in it spreading to infect an entire collection. However, localized bug-damage growth may remain isolated to the damaged portion of a single plant without spreading. | |
| |
| ===== Treatment & Management ===== | ===== Cultivation Notes ===== |
| *Note: The community authority, Gee Bee, did not participate in this discussion. The following recommendations reflect the consensus of experienced growers in the thread.* | Proper management of suspected Witch's Broom is critical to protecting a collection: |
| | * **Quarantine:** Immediately isolate any suspect plant. Keeping it quarantined at a significant distance (e.g., 200 yards) from the main collection is highly recommended while monitoring the growth. |
| | * **Culling:** If infectious phytoplasmic (MLO) Witch's Broom is suspected, the safest course of action is to burn or trash the plant, pot and all, to prevent rapid spread. |
| | * **Surgery:** For valuable specimens showing localized or pest-induced damage, growers have successfully excised the affected parts. Use a knife sterilized with isopropyl alcohol to cut away the clustered growth. Dust the wounds with sulfur. Keep quarantined for an extended time period to ensure broom type growth does not reappear. |
| | * **Pest Management:** Closely inspect the grow area for pests. Treat for whatever pests are present. This should help prevent spread and reintroduction. |
| |
| * **Quarantine:** Immediately isolate the suspected plant far away from the rest of the collection to prevent potential spread. | <ifauth @trusted_grower,@admin> |
| * **Excision:** Cut off the affected or damaged growth point entirely. | ===== Community Discussion & Citations ===== |
| * **Wound Care:** Dust the fresh cut with sulfur and allow it to heal. | //Analysis of the discussion.// |
| * **Observation:** Monitor the plant closely after isolation to determine if the abnormal growth continues or if the plant recovers. | The community discussion centers on distinguishing true infectious Witch's Broom from benign look-alikes. Experienced growers emphasize that "Witch's Broom" is often used as a catch-all term for a set of symptoms rather than a single disease. While the phytoplasmic (MLO) variant is highly contagious and destructive, many cases of "brooming" are actually caused by localized pest damage (such as mealybugs or caterpillars terminating the meristem) or genetic mutations. |
| |
| ===== Reported Cases ===== | In particular, crosses involving the cultivar "Olivia" are noted for naturally producing funky, highly clustered growth points that can easily be mistaken for the disease. Topic experts advise adjusting environmental factors like nutrients and lighting before panicking, as these genetic lines frequently exhibit systemic responses to cultivation inputs. |
| ^ Date ^ Reporter ^ Diagnosed by ^ Confidence ^ Key note / quote ^ | |
| | 2026-06-22 | John Alan Steigenberger | Thomas Lauritzen | 6 | "Does not look like WB to me. Looks like a active grow point. WB will be 3X this 'clustered'." | | |
| | 2026-06-22 | Loic Martin | Loic Martin | 6 | "I had this after bug dammage.... Kept growing like that on the damaged part... I ended cutting off that part....The rest of the plant was fine" | | |
| |
| ===== Notes & Contradictions ===== | ^ Date ^ Speaker ^ Key Insight/Quote ^ |
| Gee Bee did not participate in this discussion thread. | | 2026 (approx) | Gee Bee | "No, Olivia is known for funky growth in crosses. This is systemic environmental; nutes, lighting etc." | |
| | | 2026 (approx) | Kelly Beth Costello | "I would burn it, pot and all or it spreads fast." | |
| | | 2026 (approx) | Sam Payne | "Witches broom is the name for a set of symptoms not a specific disease. So this looks like witches broom caused by pest insects, once treated it hopefully will clear up. Phytoplasmic bacterial witches broom is the nasty contagious hard to treat one that people burn plants about." | |
| | | 2026 (approx) | Thomas Lauritzen | "Does not look like WB to me. Looks like a active grow point. WB will be 3X this "clustered". You are good" | |
| | | 2026 (approx) | Matt Olson | "I'm not an expert on the broom, but I don't think it's brooming. If this was just a regular non monstrose cactus, I would be more suspicious. Which is broom, does affect the hormone levels But this just could be the mutation." | |
| | | 2026 (approx) | ScrapGoat Benjamin | "Oh yeah. My opinion id say quarantine. cut it off. Dust with sulfur. Let it heal. Or you could let it go but if it actually is broom and you let it go you might regret it" | |
| | | 2026 (approx) | Cody Hinds | "witch's broom isn't a disease, it is a symptom. Sometimes it is caused by viral, fungal, bacterial, or insect infestations, sometimes it is caused by heat or sun stress." | |
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| There is an ongoing debate regarding whether clustered growth on monstrose cultivars is a sign of disease or simply a expression of the plant's natural mutation. While some growers advise immediate cutting and quarantine out of caution to prevent a collection-wide outbreak, others note that pest damage can mimic these symptoms without presenting a systemic threat to the plant. | ===== Contributor Confidence ===== |
| | //Visible to trusted reviewers only.// |
| | |
| | ^ Contributor ^ Confidence ^ |
| | | Gee Bee | 10/10 | |
| | | Kelly Beth Costello | 8/10 | |
| | | Sam Payne | 8/10 | |
| | | Thomas Lauritzen | 7/10 | |
| | | Matt Olson | 7/10 | |
| | | ScrapGoat Benjamin | 6/10 | |
| | | Cody Hinds | 6/10 | |
| | |
| | |
| | ===== Credibility Notes ===== |
| | * **Gee Bee:** Recognized as a premier topic authority on Trichocereus genetics. Their expertise on "Olivia" crosses and environmental growth triggers overrides general community speculation. |
| | * **Kelly Beth Costello:** Provided direct scientific literature citations regarding Mycoplasma-Like Organisms (MLO) and offered clear, actionable biosecurity advice. |
| | * **Sam Payne:** Provided a highly detailed, accurate botanical breakdown distinguishing between pest-induced meristem termination and contagious phytoplasmic infections. |
| | * **Thomas Lauritzen & Matt Olson:** Offered consistent, detailed diagnostic criteria regarding clustering density, hormonal shifts, and genetic mutations. |
| | * **ScrapGoat Benjamin & Cody Hinds:** Provided solid, practical cultivation advice and accurate conceptual definitions of the symptom, backed by years of observation. |
| | </ifauth> |
| |
| ===== References ===== | |
| * **Contributors:** Maria Megalogeni, Loic Martin, ScrapGoat Benjamin, John Alan Steigenberger, Thomas Traweek, Shane Thomas, Snooty Nose Kennels, Peter Nehen, Thomas Lauritzen, Matt Olson, Cheyenne Dennis, Bob Makershoe. | |
| * **Photos:** John Alan Steigenberger. | |
